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Re: A case of death wobble today
As an engineer, you will notice the TJ uses control arms that form
a radius, mounted behind the front axle so the higher the lift the more castor he looses as the axle swings down and towards the back of the car. So in a braking dip he would in temporally gain some of those degrees back. Of course, Terry here, has Real Jeep leaf springs, that are not effected by height. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ Roy J wrote: > > Since this seems to be the argument of the week, I went off and > did some calculations. Sigh. I hate being an engineer. > > A while back there was a guy from the east coast, helicopter > pilot, etc that had a built TJ (sorry I can't pull up his name) > and we got into the discussion of DW on the TJ. He finally > convinced me that big tires need LESS caster than stock tires > (say about 5 degrees) rather than the 6 to 7 degrees on the > various shop specs. And that the toe in on big tires needs to be > as close to zero as you can get and still be toe in. > > The OP stated that he has the 1" lift Confer shackles (that are > 2" longer than stock) Sin (2"/45") is 2.56 degrees. So the OP is > shorting himself 2.5 degrees on the caster (unless he has added > the appropriate shims of course) Every inch lowering in the front > shaves another .6 degree off the caster. So if he hits the brakes > and gets 3" of front dive, he shaves another 2 degrees off the > caster. If he has any permamanet spring wrap, he will shave off > some more. (35" tires and a D60 probably means he pushes it a > little!) > > The OP stated that he has high mileage on his 35" tires. Most of > us have not solved the problem of perfect wear on big tires so > I'll assume that they are not worn evenly. He did not state if he > had balanced them lately but even then, did he shuck a wheel weight? > > The OP has the reversed tie rod , this changes things from what > most of us run. > > Th OP told Dynatrac about his vehicle, did he indicate he was > going to use the Confer shackles? And does Dynatrac set up the > axle for a specified caster angle??? Ie do they do factory stock > or what works?? > > When we tackle a harmonic vibration problem (and this is a > special case of the general theory) we have 4 basic methods to > deal with things: > 1) change the freqeuency of the system > 2) "Stiffen" the system to move the harmonic up higher. > 3) Dampen the system > 4) Reduce the input energy at the vibration frequency to keep if > from going off. > > In a Jeep, #1 is tough, it has to move through a range of > frequencies (speeds) > > #2 involves tightening up the slop in the system (tie rod ends, > ball joints, heavier tie rod, etc) Plus you need enough toe in to > keep the system preloaded one direction. > > #3 is the infamous steering stabilzer. > > #4 is mostly from the tires. They need to be dynamicly balanced > at the frequency in question (about 60 mph) AND they need to be > round and straight. Keep in mind that 35" tires run almost 100 > pounds a piece, I have seen them worn down with up to 1/4" cups > and waves in them. Lots of side energy available here. > > Net: I'll sit here and speculate that the actual caster is way > less than the OP thinks it is, that the tires are worn and out of > balance (not a lot but enough!), that he hit the brakes and a > bump with a bit of a turn, the whole works started to shake, and > the steering stabilzer was not up to the job of getting control > back. Take your choice of fixes, I personally prefer naturally > stable systems to ones that are subject to failure from the > fatigue of a single component. > > Cheers. > > CRWLR wrote: > > > Think of how the forks on a motorcycle are raked. A chopper goes straighat > > ahead really good, but can be a bitch to turn, and a racing bike can turn on > > a dime, but the steering is very twitchy. The most significant difference in > > these examples is the rake of the forks, and this rake is similar to the > > Caster angle. > > > > As I said earlier, caster typically does not play a large role in the > > adjustments of the front end geometry because it is pretty much set during > > manufacturing of the axle. The spring perches define the caster angle. > > Assuming the axle is the right one, the caster angle should be right. Of > > course, with custom modifications - lift - the caster angle can change > > enough to become a player in DW. > > > > Caster angle is the imaginary line through the upper and lower ball joints, > > and the center of the spindle. Properly set, the caster angle should be > > about 7° towards the rear of the vehicle. That is, the upper ball joint > > should trail the lower by about 7°. Perhaps the number is a little bit > > different in your case, but greater angles will be more stable than lesser > > angles. When the angle drops to about 4° or less, then the tires will search > > for the straight ahead position, and this sets up the DW symptoms. There is > > an easy test for Caster angle ... Go to an open area and make a Uturn, or a > > manuver that simulates what you might do when backing from a parking stall. > > Turn the steering wheel fully to one stop, then begin going and see if the > > wheel returns to center on its own, or if it remains in Turning Mode and > > requires you to physically turn back to center. If you have to drive it back > > to straight ahead, then your caster is not great enough, but if it wants to > > go to center on its own, then the caster is probably OK. > > > > In my motorcycle analogy, there are other geometry forces at play, so the > > analogy breaks down pretty quickly, but in general terms, it works pretty > > well. I am certain that my analogy will be corrected, but it works for now. > > > > My FSM says the spec for Caster angle is 6°. > > > > > > > > > > > > "Terry Jeffrey" <twjeffrey@hotmail.com> wrote in message > > news:a5SZb.4126$aT1.454@newsread1.news.pas.earthli nk.net... > > > >>The ball joints appear to be good. I did the push-pull-raised-tire test > > > > and > > > >>it checked out Ok. All the rod ends are tight and lubed. I'll get the > >>caster checked out next week. Explain, if you will, why caster would be a > >>player in DW. This could be my problem. If the caster angle is off, > >>wouldn't this only cause the vehicle to pull to one side or the other? > >> > >>It was suggested to move the steering stabilizer from the drag link to the > >>tie rod. When I did this, I still got the same DW. I thought I felt a > >>little air in the stabilizer at the extended end while testing it, and > > > > will > > > >>replace it as soon as I can find one. > >> > >>Your track bar comment is noted. I'd like to leave it off all together > >>because real estate up front is a premium right now with the Dana60. But > >>will put it back on nice and tight and put the DW to the test again. > >> > >>Thanks again, > >>Terry. > >> > >> > >> > >> > >>"CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message > >>news:103foc9kj445236@corp.supernews.com... > >> > >>>If all of that stuff is new, I would not think the steering stabalizer > >> > >>would > >> > >>>be so significant. Did you attempt the tests that I described? (If I > >>>described something incorrectly, did you try what might have been > >> > >>suggested > >> > >>>to correct me?) > >>> > >>>If you suspect the track bar is worn, and causing a problem with > >> > >>looseness, > >> > >>>then removing the trackbar altogether is not much of a confirmation > > > > test. > > > >>If > >> > >>>yo had no trackbar, and complained of DW, then put the bar on to see if > >> > >>the > >> > >>>DW went away, then you would have a reasonable diagnostic test. Taking > > > > the > > > >>>trackbar off is the same thing as having one on that had worn bushings. > >>> |
Re: A case of death wobble today
As an engineer, you will notice the TJ uses control arms that form
a radius, mounted behind the front axle so the higher the lift the more castor he looses as the axle swings down and towards the back of the car. So in a braking dip he would in temporally gain some of those degrees back. Of course, Terry here, has Real Jeep leaf springs, that are not effected by height. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ Roy J wrote: > > Since this seems to be the argument of the week, I went off and > did some calculations. Sigh. I hate being an engineer. > > A while back there was a guy from the east coast, helicopter > pilot, etc that had a built TJ (sorry I can't pull up his name) > and we got into the discussion of DW on the TJ. He finally > convinced me that big tires need LESS caster than stock tires > (say about 5 degrees) rather than the 6 to 7 degrees on the > various shop specs. And that the toe in on big tires needs to be > as close to zero as you can get and still be toe in. > > The OP stated that he has the 1" lift Confer shackles (that are > 2" longer than stock) Sin (2"/45") is 2.56 degrees. So the OP is > shorting himself 2.5 degrees on the caster (unless he has added > the appropriate shims of course) Every inch lowering in the front > shaves another .6 degree off the caster. So if he hits the brakes > and gets 3" of front dive, he shaves another 2 degrees off the > caster. If he has any permamanet spring wrap, he will shave off > some more. (35" tires and a D60 probably means he pushes it a > little!) > > The OP stated that he has high mileage on his 35" tires. Most of > us have not solved the problem of perfect wear on big tires so > I'll assume that they are not worn evenly. He did not state if he > had balanced them lately but even then, did he shuck a wheel weight? > > The OP has the reversed tie rod , this changes things from what > most of us run. > > Th OP told Dynatrac about his vehicle, did he indicate he was > going to use the Confer shackles? And does Dynatrac set up the > axle for a specified caster angle??? Ie do they do factory stock > or what works?? > > When we tackle a harmonic vibration problem (and this is a > special case of the general theory) we have 4 basic methods to > deal with things: > 1) change the freqeuency of the system > 2) "Stiffen" the system to move the harmonic up higher. > 3) Dampen the system > 4) Reduce the input energy at the vibration frequency to keep if > from going off. > > In a Jeep, #1 is tough, it has to move through a range of > frequencies (speeds) > > #2 involves tightening up the slop in the system (tie rod ends, > ball joints, heavier tie rod, etc) Plus you need enough toe in to > keep the system preloaded one direction. > > #3 is the infamous steering stabilzer. > > #4 is mostly from the tires. They need to be dynamicly balanced > at the frequency in question (about 60 mph) AND they need to be > round and straight. Keep in mind that 35" tires run almost 100 > pounds a piece, I have seen them worn down with up to 1/4" cups > and waves in them. Lots of side energy available here. > > Net: I'll sit here and speculate that the actual caster is way > less than the OP thinks it is, that the tires are worn and out of > balance (not a lot but enough!), that he hit the brakes and a > bump with a bit of a turn, the whole works started to shake, and > the steering stabilzer was not up to the job of getting control > back. Take your choice of fixes, I personally prefer naturally > stable systems to ones that are subject to failure from the > fatigue of a single component. > > Cheers. > > CRWLR wrote: > > > Think of how the forks on a motorcycle are raked. A chopper goes straighat > > ahead really good, but can be a bitch to turn, and a racing bike can turn on > > a dime, but the steering is very twitchy. The most significant difference in > > these examples is the rake of the forks, and this rake is similar to the > > Caster angle. > > > > As I said earlier, caster typically does not play a large role in the > > adjustments of the front end geometry because it is pretty much set during > > manufacturing of the axle. The spring perches define the caster angle. > > Assuming the axle is the right one, the caster angle should be right. Of > > course, with custom modifications - lift - the caster angle can change > > enough to become a player in DW. > > > > Caster angle is the imaginary line through the upper and lower ball joints, > > and the center of the spindle. Properly set, the caster angle should be > > about 7° towards the rear of the vehicle. That is, the upper ball joint > > should trail the lower by about 7°. Perhaps the number is a little bit > > different in your case, but greater angles will be more stable than lesser > > angles. When the angle drops to about 4° or less, then the tires will search > > for the straight ahead position, and this sets up the DW symptoms. There is > > an easy test for Caster angle ... Go to an open area and make a Uturn, or a > > manuver that simulates what you might do when backing from a parking stall. > > Turn the steering wheel fully to one stop, then begin going and see if the > > wheel returns to center on its own, or if it remains in Turning Mode and > > requires you to physically turn back to center. If you have to drive it back > > to straight ahead, then your caster is not great enough, but if it wants to > > go to center on its own, then the caster is probably OK. > > > > In my motorcycle analogy, there are other geometry forces at play, so the > > analogy breaks down pretty quickly, but in general terms, it works pretty > > well. I am certain that my analogy will be corrected, but it works for now. > > > > My FSM says the spec for Caster angle is 6°. > > > > > > > > > > > > "Terry Jeffrey" <twjeffrey@hotmail.com> wrote in message > > news:a5SZb.4126$aT1.454@newsread1.news.pas.earthli nk.net... > > > >>The ball joints appear to be good. I did the push-pull-raised-tire test > > > > and > > > >>it checked out Ok. All the rod ends are tight and lubed. I'll get the > >>caster checked out next week. Explain, if you will, why caster would be a > >>player in DW. This could be my problem. If the caster angle is off, > >>wouldn't this only cause the vehicle to pull to one side or the other? > >> > >>It was suggested to move the steering stabilizer from the drag link to the > >>tie rod. When I did this, I still got the same DW. I thought I felt a > >>little air in the stabilizer at the extended end while testing it, and > > > > will > > > >>replace it as soon as I can find one. > >> > >>Your track bar comment is noted. I'd like to leave it off all together > >>because real estate up front is a premium right now with the Dana60. But > >>will put it back on nice and tight and put the DW to the test again. > >> > >>Thanks again, > >>Terry. > >> > >> > >> > >> > >>"CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message > >>news:103foc9kj445236@corp.supernews.com... > >> > >>>If all of that stuff is new, I would not think the steering stabalizer > >> > >>would > >> > >>>be so significant. Did you attempt the tests that I described? (If I > >>>described something incorrectly, did you try what might have been > >> > >>suggested > >> > >>>to correct me?) > >>> > >>>If you suspect the track bar is worn, and causing a problem with > >> > >>looseness, > >> > >>>then removing the trackbar altogether is not much of a confirmation > > > > test. > > > >>If > >> > >>>yo had no trackbar, and complained of DW, then put the bar on to see if > >> > >>the > >> > >>>DW went away, then you would have a reasonable diagnostic test. Taking > > > > the > > > >>>trackbar off is the same thing as having one on that had worn bushings. > >>> |
Re: A case of death wobble today
On Sun, 22 Feb 2004 21:44:14 -0800, L.W.(ßill) ------ III
<----------@cox.net> wrote: > As an engineer, you will notice the TJ uses control arms that form >a radius, mounted behind the front axle so the higher the lift the more >castor he looses as the axle swings down and towards the back of the >car. So in a braking dip he would in temporally gain some of those >degrees back. Of course, Terry here, has Real Jeep leaf springs, that >are not effected by height. They would be if some of the height is gained by using the lift shackles. I was looking at these as a cheap way to lift my YJ, but it didn't take an engineer to tell me that lifing one end of the springs is going to rotate the axle and thus change the castor angles. -- Old Crow '82 Shovelhead FLT 92" 'Pearl' '95 Jeep YJ Rio Grande ASE Certified Master Auto Tech + L1 TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
On Sun, 22 Feb 2004 21:44:14 -0800, L.W.(ßill) ------ III
<----------@cox.net> wrote: > As an engineer, you will notice the TJ uses control arms that form >a radius, mounted behind the front axle so the higher the lift the more >castor he looses as the axle swings down and towards the back of the >car. So in a braking dip he would in temporally gain some of those >degrees back. Of course, Terry here, has Real Jeep leaf springs, that >are not effected by height. They would be if some of the height is gained by using the lift shackles. I was looking at these as a cheap way to lift my YJ, but it didn't take an engineer to tell me that lifing one end of the springs is going to rotate the axle and thus change the castor angles. -- Old Crow '82 Shovelhead FLT 92" 'Pearl' '95 Jeep YJ Rio Grande ASE Certified Master Auto Tech + L1 TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
On Sun, 22 Feb 2004 21:44:14 -0800, L.W.(ßill) ------ III
<----------@cox.net> wrote: > As an engineer, you will notice the TJ uses control arms that form >a radius, mounted behind the front axle so the higher the lift the more >castor he looses as the axle swings down and towards the back of the >car. So in a braking dip he would in temporally gain some of those >degrees back. Of course, Terry here, has Real Jeep leaf springs, that >are not effected by height. They would be if some of the height is gained by using the lift shackles. I was looking at these as a cheap way to lift my YJ, but it didn't take an engineer to tell me that lifing one end of the springs is going to rotate the axle and thus change the castor angles. -- Old Crow '82 Shovelhead FLT 92" 'Pearl' '95 Jeep YJ Rio Grande ASE Certified Master Auto Tech + L1 TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
Have you tried going to your webmail site and using SPAM/VIRUS blocking
there? If you do that, your unwanted emails will get automatically deleted and won't clog your acct up. There is no reason to change email addresses in most cases. Roy J wrote: > Actually, since you see the stabilizers on most later model 4x4's (but > not most other vehicles) I would SPECULATE that they are there to cut > the shock loading to the steering wheel and driver when you hit a rock > or pot hole. Without one, the steering wheel will spin violently, the > front wheel will twist up against it's stop. Not a good thing at any > kind of speed. The old tractors commonly had a steering knob bolted to > the steering wheel, quite a few broken wrists as a result. Power > steering calms this down a lot, but you still can get quite a bit of > feed back from the wheels. > > Oh, and I can easily block the virus loads with a decent anti virus. The > problem was that I do not have 'always on' ISP service, my ISP would > shut down my account when it hit 15mb worth of files. As in about 4 > hours. A guy has to sleep sometimes. -- __________________________________________________ _________ tw 03 TJ Rubicon - Rubicon Express 4.5" 01 XJ Sport There is a very fine line between "hobby" and "mental illness." -- Dave Barry Pronunciation: 'jEp Function: noun Date: 1940 Etymology: probably from g. p. (abbreviation of general purpose) A small general-purpose motor vehicle with 80-inch wheelbase, 1/4-ton capacity, and four-wheel drive used by the U.S. army in World War II. (Please remove the OBVIOUS to reply by email) __________________________________________________ _________ |
Re: A case of death wobble today
Have you tried going to your webmail site and using SPAM/VIRUS blocking
there? If you do that, your unwanted emails will get automatically deleted and won't clog your acct up. There is no reason to change email addresses in most cases. Roy J wrote: > Actually, since you see the stabilizers on most later model 4x4's (but > not most other vehicles) I would SPECULATE that they are there to cut > the shock loading to the steering wheel and driver when you hit a rock > or pot hole. Without one, the steering wheel will spin violently, the > front wheel will twist up against it's stop. Not a good thing at any > kind of speed. The old tractors commonly had a steering knob bolted to > the steering wheel, quite a few broken wrists as a result. Power > steering calms this down a lot, but you still can get quite a bit of > feed back from the wheels. > > Oh, and I can easily block the virus loads with a decent anti virus. The > problem was that I do not have 'always on' ISP service, my ISP would > shut down my account when it hit 15mb worth of files. As in about 4 > hours. A guy has to sleep sometimes. -- __________________________________________________ _________ tw 03 TJ Rubicon - Rubicon Express 4.5" 01 XJ Sport There is a very fine line between "hobby" and "mental illness." -- Dave Barry Pronunciation: 'jEp Function: noun Date: 1940 Etymology: probably from g. p. (abbreviation of general purpose) A small general-purpose motor vehicle with 80-inch wheelbase, 1/4-ton capacity, and four-wheel drive used by the U.S. army in World War II. (Please remove the OBVIOUS to reply by email) __________________________________________________ _________ |
Re: A case of death wobble today
Have you tried going to your webmail site and using SPAM/VIRUS blocking
there? If you do that, your unwanted emails will get automatically deleted and won't clog your acct up. There is no reason to change email addresses in most cases. Roy J wrote: > Actually, since you see the stabilizers on most later model 4x4's (but > not most other vehicles) I would SPECULATE that they are there to cut > the shock loading to the steering wheel and driver when you hit a rock > or pot hole. Without one, the steering wheel will spin violently, the > front wheel will twist up against it's stop. Not a good thing at any > kind of speed. The old tractors commonly had a steering knob bolted to > the steering wheel, quite a few broken wrists as a result. Power > steering calms this down a lot, but you still can get quite a bit of > feed back from the wheels. > > Oh, and I can easily block the virus loads with a decent anti virus. The > problem was that I do not have 'always on' ISP service, my ISP would > shut down my account when it hit 15mb worth of files. As in about 4 > hours. A guy has to sleep sometimes. -- __________________________________________________ _________ tw 03 TJ Rubicon - Rubicon Express 4.5" 01 XJ Sport There is a very fine line between "hobby" and "mental illness." -- Dave Barry Pronunciation: 'jEp Function: noun Date: 1940 Etymology: probably from g. p. (abbreviation of general purpose) A small general-purpose motor vehicle with 80-inch wheelbase, 1/4-ton capacity, and four-wheel drive used by the U.S. army in World War II. (Please remove the OBVIOUS to reply by email) __________________________________________________ _________ |
Re: A case of death wobble today
Yep!
Del Rawlins wrote: > In <1Yf_b.131$pT1.86178@news.uswest.net> Roy J wrote: > > >>A while back there was a guy from the east coast, helicopter=20 >>pilot, etc that had a built TJ (sorry I can't pull up his name)=20 >>and we got into the discussion of DW on the TJ. He finally=20 >>convinced me that big tires need LESS caster than stock tires=20 > > > That sounds like Harry B. > > ---------------------------------------------------- > Del Rawlins- del@_kills_spammers_rawlinsbrothers.org > Remove _kills_spammers_ to reply via email. > Unofficial Bearhawk FAQ website: > http://www.rawlinsbrothers.org/bhfaq/ |
Re: A case of death wobble today
Yep!
Del Rawlins wrote: > In <1Yf_b.131$pT1.86178@news.uswest.net> Roy J wrote: > > >>A while back there was a guy from the east coast, helicopter=20 >>pilot, etc that had a built TJ (sorry I can't pull up his name)=20 >>and we got into the discussion of DW on the TJ. He finally=20 >>convinced me that big tires need LESS caster than stock tires=20 > > > That sounds like Harry B. > > ---------------------------------------------------- > Del Rawlins- del@_kills_spammers_rawlinsbrothers.org > Remove _kills_spammers_ to reply via email. > Unofficial Bearhawk FAQ website: > http://www.rawlinsbrothers.org/bhfaq/ |
Re: A case of death wobble today
Yep!
Del Rawlins wrote: > In <1Yf_b.131$pT1.86178@news.uswest.net> Roy J wrote: > > >>A while back there was a guy from the east coast, helicopter=20 >>pilot, etc that had a built TJ (sorry I can't pull up his name)=20 >>and we got into the discussion of DW on the TJ. He finally=20 >>convinced me that big tires need LESS caster than stock tires=20 > > > That sounds like Harry B. > > ---------------------------------------------------- > Del Rawlins- del@_kills_spammers_rawlinsbrothers.org > Remove _kills_spammers_ to reply via email. > Unofficial Bearhawk FAQ website: > http://www.rawlinsbrothers.org/bhfaq/ |
Re: A case of death wobble today
I have an ISP provider that offers NO spam control options. And I
am wedded to that provider for other reasons that tend to raise my blood pressure. I'd switch in a minute if I could. My ISP only allows 2 e-mail boxes, both are in use. Most good ones allow 10 or so, makes it easy to change addresses when the spam traffic gets too heavy. Use two for business, rest can be used for public exposure. I have software that allows me to look at and delete the messages while still on the POP3 server. But I have not found an antivirus, anti spam software that runs in an automatic mode to a POP3 server. The other option was to download all the crap and delete it locally. The SVEN hit started at 4mb per hour, dwindled down to ONLY 1mb per hour a month later. I'm back on the air now but I have the bogus address for NG stuff. Sigh. twaldron wrote: > Have you tried going to your webmail site and using SPAM/VIRUS blocking > there? If you do that, your unwanted emails will get automatically > deleted and won't clog your acct up. There is no reason to change email > addresses in most cases. > > Roy J wrote: > >> Actually, since you see the stabilizers on most later model 4x4's (but >> not most other vehicles) I would SPECULATE that they are there to cut >> the shock loading to the steering wheel and driver when you hit a rock >> or pot hole. Without one, the steering wheel will spin violently, the >> front wheel will twist up against it's stop. Not a good thing at any >> kind of speed. The old tractors commonly had a steering knob bolted to >> the steering wheel, quite a few broken wrists as a result. Power >> steering calms this down a lot, but you still can get quite a bit of >> feed back from the wheels. >> >> Oh, and I can easily block the virus loads with a decent anti virus. >> The problem was that I do not have 'always on' ISP service, my ISP >> would shut down my account when it hit 15mb worth of files. As in >> about 4 hours. A guy has to sleep sometimes. > > |
Re: A case of death wobble today
I have an ISP provider that offers NO spam control options. And I
am wedded to that provider for other reasons that tend to raise my blood pressure. I'd switch in a minute if I could. My ISP only allows 2 e-mail boxes, both are in use. Most good ones allow 10 or so, makes it easy to change addresses when the spam traffic gets too heavy. Use two for business, rest can be used for public exposure. I have software that allows me to look at and delete the messages while still on the POP3 server. But I have not found an antivirus, anti spam software that runs in an automatic mode to a POP3 server. The other option was to download all the crap and delete it locally. The SVEN hit started at 4mb per hour, dwindled down to ONLY 1mb per hour a month later. I'm back on the air now but I have the bogus address for NG stuff. Sigh. twaldron wrote: > Have you tried going to your webmail site and using SPAM/VIRUS blocking > there? If you do that, your unwanted emails will get automatically > deleted and won't clog your acct up. There is no reason to change email > addresses in most cases. > > Roy J wrote: > >> Actually, since you see the stabilizers on most later model 4x4's (but >> not most other vehicles) I would SPECULATE that they are there to cut >> the shock loading to the steering wheel and driver when you hit a rock >> or pot hole. Without one, the steering wheel will spin violently, the >> front wheel will twist up against it's stop. Not a good thing at any >> kind of speed. The old tractors commonly had a steering knob bolted to >> the steering wheel, quite a few broken wrists as a result. Power >> steering calms this down a lot, but you still can get quite a bit of >> feed back from the wheels. >> >> Oh, and I can easily block the virus loads with a decent anti virus. >> The problem was that I do not have 'always on' ISP service, my ISP >> would shut down my account when it hit 15mb worth of files. As in >> about 4 hours. A guy has to sleep sometimes. > > |
Re: A case of death wobble today
I have an ISP provider that offers NO spam control options. And I
am wedded to that provider for other reasons that tend to raise my blood pressure. I'd switch in a minute if I could. My ISP only allows 2 e-mail boxes, both are in use. Most good ones allow 10 or so, makes it easy to change addresses when the spam traffic gets too heavy. Use two for business, rest can be used for public exposure. I have software that allows me to look at and delete the messages while still on the POP3 server. But I have not found an antivirus, anti spam software that runs in an automatic mode to a POP3 server. The other option was to download all the crap and delete it locally. The SVEN hit started at 4mb per hour, dwindled down to ONLY 1mb per hour a month later. I'm back on the air now but I have the bogus address for NG stuff. Sigh. twaldron wrote: > Have you tried going to your webmail site and using SPAM/VIRUS blocking > there? If you do that, your unwanted emails will get automatically > deleted and won't clog your acct up. There is no reason to change email > addresses in most cases. > > Roy J wrote: > >> Actually, since you see the stabilizers on most later model 4x4's (but >> not most other vehicles) I would SPECULATE that they are there to cut >> the shock loading to the steering wheel and driver when you hit a rock >> or pot hole. Without one, the steering wheel will spin violently, the >> front wheel will twist up against it's stop. Not a good thing at any >> kind of speed. The old tractors commonly had a steering knob bolted to >> the steering wheel, quite a few broken wrists as a result. Power >> steering calms this down a lot, but you still can get quite a bit of >> feed back from the wheels. >> >> Oh, and I can easily block the virus loads with a decent anti virus. >> The problem was that I do not have 'always on' ISP service, my ISP >> would shut down my account when it hit 15mb worth of files. As in >> about 4 hours. A guy has to sleep sometimes. > > |
Re: A case of death wobble today
Except putting a longer shackle on increases it's leverage on the
spring, almost instantly pulling the arc out of the spring, for no change. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ Old Crow wrote: > > They would be if some of the height is gained by using the lift > shackles. I was looking at these as a cheap way to lift my YJ, but it > didn't take an engineer to tell me that lifing one end of the springs > is going to rotate the axle and thus change the castor angles. > > -- > Old Crow > '82 Shovelhead FLT 92" 'Pearl' > '95 Jeep YJ Rio Grande > ASE Certified Master Auto Tech + L1 > TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
Except putting a longer shackle on increases it's leverage on the
spring, almost instantly pulling the arc out of the spring, for no change. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ Old Crow wrote: > > They would be if some of the height is gained by using the lift > shackles. I was looking at these as a cheap way to lift my YJ, but it > didn't take an engineer to tell me that lifing one end of the springs > is going to rotate the axle and thus change the castor angles. > > -- > Old Crow > '82 Shovelhead FLT 92" 'Pearl' > '95 Jeep YJ Rio Grande > ASE Certified Master Auto Tech + L1 > TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
Except putting a longer shackle on increases it's leverage on the
spring, almost instantly pulling the arc out of the spring, for no change. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ Old Crow wrote: > > They would be if some of the height is gained by using the lift > shackles. I was looking at these as a cheap way to lift my YJ, but it > didn't take an engineer to tell me that lifing one end of the springs > is going to rotate the axle and thus change the castor angles. > > -- > Old Crow > '82 Shovelhead FLT 92" 'Pearl' > '95 Jeep YJ Rio Grande > ASE Certified Master Auto Tech + L1 > TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
My '81 FSM makes it look as though the CJs that year made the stabalizer an
option. Mine is certainly NOT installed in the same manner as the manual suggests it should be, therefore my guess is that one of the POs installed it. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403973BB.1E0E50B1@cox.net... > My '68 CJ-5 is the only 4x4 I've seen that wasn't sold new with > stabilizer. Everything from my '72 Ford on had one stock. Look under > your old Chevy or motorhome. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > It appears to have been an optional part as late as '81. > > > > I happen to agree that the stabalizer is probably masking a more serious > > problem that if it was not there, the DW symptoms would not be so severe. > > > > If the steering stabalizer by itself fixes this problem, I'll be seriously > > amazed. It could, I suppose. But I think there are underlying problems at > > play here. |
Re: A case of death wobble today
My '81 FSM makes it look as though the CJs that year made the stabalizer an
option. Mine is certainly NOT installed in the same manner as the manual suggests it should be, therefore my guess is that one of the POs installed it. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403973BB.1E0E50B1@cox.net... > My '68 CJ-5 is the only 4x4 I've seen that wasn't sold new with > stabilizer. Everything from my '72 Ford on had one stock. Look under > your old Chevy or motorhome. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > It appears to have been an optional part as late as '81. > > > > I happen to agree that the stabalizer is probably masking a more serious > > problem that if it was not there, the DW symptoms would not be so severe. > > > > If the steering stabalizer by itself fixes this problem, I'll be seriously > > amazed. It could, I suppose. But I think there are underlying problems at > > play here. |
Re: A case of death wobble today
My '81 FSM makes it look as though the CJs that year made the stabalizer an
option. Mine is certainly NOT installed in the same manner as the manual suggests it should be, therefore my guess is that one of the POs installed it. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403973BB.1E0E50B1@cox.net... > My '68 CJ-5 is the only 4x4 I've seen that wasn't sold new with > stabilizer. Everything from my '72 Ford on had one stock. Look under > your old Chevy or motorhome. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > It appears to have been an optional part as late as '81. > > > > I happen to agree that the stabalizer is probably masking a more serious > > problem that if it was not there, the DW symptoms would not be so severe. > > > > If the steering stabalizer by itself fixes this problem, I'll be seriously > > amazed. It could, I suppose. But I think there are underlying problems at > > play here. |
Re: A case of death wobble today
I always was told that there are spambots that search Usenet to harvest
email address that reside in the headers. I am convinced that my address was harvested, probably only once, and then was sold on the open market. In any case, I was forced to put a fake address in my newsgroup headers in the effort to hope that the spambots would be rendered harmless to me. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:40397246.DC22F645@cox.net... > The spam you get is not from little people individually harvesting > the addresses from the news groups. Judging my My wife's address that is > used maybe once a year to test, I'd say COX.net is responsible for > selling that address. Almost nothing goes the the addresses in my > signature. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > Wait a second there, I take responsibility but use a fake email address. I > > am not opposed to the discussion I generate, but I can't stand the spam that > > I get when I use my real address. |
Re: A case of death wobble today
I always was told that there are spambots that search Usenet to harvest
email address that reside in the headers. I am convinced that my address was harvested, probably only once, and then was sold on the open market. In any case, I was forced to put a fake address in my newsgroup headers in the effort to hope that the spambots would be rendered harmless to me. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:40397246.DC22F645@cox.net... > The spam you get is not from little people individually harvesting > the addresses from the news groups. Judging my My wife's address that is > used maybe once a year to test, I'd say COX.net is responsible for > selling that address. Almost nothing goes the the addresses in my > signature. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > Wait a second there, I take responsibility but use a fake email address. I > > am not opposed to the discussion I generate, but I can't stand the spam that > > I get when I use my real address. |
Re: A case of death wobble today
I always was told that there are spambots that search Usenet to harvest
email address that reside in the headers. I am convinced that my address was harvested, probably only once, and then was sold on the open market. In any case, I was forced to put a fake address in my newsgroup headers in the effort to hope that the spambots would be rendered harmless to me. "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:40397246.DC22F645@cox.net... > The spam you get is not from little people individually harvesting > the addresses from the news groups. Judging my My wife's address that is > used maybe once a year to test, I'd say COX.net is responsible for > selling that address. Almost nothing goes the the addresses in my > signature. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > Wait a second there, I take responsibility but use a fake email address. I > > am not opposed to the discussion I generate, but I can't stand the spam that > > I get when I use my real address. |
Re: A case of death wobble today
Hi Jeff,
Probably, the previous owner did move the dampener for you, as I did on my '78 Bronco, but I left the stock one in the stock position and just added one to the position where is will do some good, just like Daimler moved it to the axle, tie rod position: http://www.----------.com/JWStabalizer.jpg from the drag link. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > My '81 FSM makes it look as though the CJs that year made the stabalizer an > option. Mine is certainly NOT installed in the same manner as the manual > suggests it should be, therefore my guess is that one of the POs installed > it. |
Re: A case of death wobble today
Hi Jeff,
Probably, the previous owner did move the dampener for you, as I did on my '78 Bronco, but I left the stock one in the stock position and just added one to the position where is will do some good, just like Daimler moved it to the axle, tie rod position: http://www.----------.com/JWStabalizer.jpg from the drag link. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > My '81 FSM makes it look as though the CJs that year made the stabalizer an > option. Mine is certainly NOT installed in the same manner as the manual > suggests it should be, therefore my guess is that one of the POs installed > it. |
Re: A case of death wobble today
Hi Jeff,
Probably, the previous owner did move the dampener for you, as I did on my '78 Bronco, but I left the stock one in the stock position and just added one to the position where is will do some good, just like Daimler moved it to the axle, tie rod position: http://www.----------.com/JWStabalizer.jpg from the drag link. God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > My '81 FSM makes it look as though the CJs that year made the stabalizer an > option. Mine is certainly NOT installed in the same manner as the manual > suggests it should be, therefore my guess is that one of the POs installed > it. |
Re: A case of death wobble today
Good luck.
God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > I always was told that there are spambots that search Usenet to harvest > email address that reside in the headers. I am convinced that my address was > harvested, probably only once, and then was sold on the open market. In any > case, I was forced to put a fake address in my newsgroup headers in the > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
Good luck.
God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > I always was told that there are spambots that search Usenet to harvest > email address that reside in the headers. I am convinced that my address was > harvested, probably only once, and then was sold on the open market. In any > case, I was forced to put a fake address in my newsgroup headers in the > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
Good luck.
God Bless America, ßill O|||||||O mailto:-------------------- http://www.----------.com/ CRWLR wrote: > > I always was told that there are spambots that search Usenet to harvest > email address that reside in the headers. I am convinced that my address was > harvested, probably only once, and then was sold on the open market. In any > case, I was forced to put a fake address in my newsgroup headers in the > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
It worked, except that my address has already been sold at least once, and
probably thousands of times. I get more spam from Korea ... "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403A612D.9544C785@cox.net... > Good luck. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > I always was told that there are spambots that search Usenet to harvest > > email address that reside in the headers. I am convinced that my address was > > harvested, probably only once, and then was sold on the open market. In any > > case, I was forced to put a fake address in my newsgroup headers in the > > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
It worked, except that my address has already been sold at least once, and
probably thousands of times. I get more spam from Korea ... "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403A612D.9544C785@cox.net... > Good luck. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > I always was told that there are spambots that search Usenet to harvest > > email address that reside in the headers. I am convinced that my address was > > harvested, probably only once, and then was sold on the open market. In any > > case, I was forced to put a fake address in my newsgroup headers in the > > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
It worked, except that my address has already been sold at least once, and
probably thousands of times. I get more spam from Korea ... "L.W. (ßill) ------ III" <----------@cox.net> wrote in message news:403A612D.9544C785@cox.net... > Good luck. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > CRWLR wrote: > > > > I always was told that there are spambots that search Usenet to harvest > > email address that reside in the headers. I am convinced that my address was > > harvested, probably only once, and then was sold on the open market. In any > > case, I was forced to put a fake address in my newsgroup headers in the > > effort to hope that the spambots would be rendered harmless to me. |
Re: A case of death wobble today
Mike, please consider a more optimistic outlook on things, my friend. ;-)
Life's too short to not be. Terry. "Mike Romain" <romainm@sympatico.ca> wrote in message news:40393109.59C41E4B@sympatico.ca... > Ok, so you have a custom, built all to crap unit, eh.... > > I have one pretty easy check 'maybe' for you... > > On a stock Jeep front end, the pinion face is straight up and down. > > So the proper caster angle corresponds to a straight up and down pinion. > > Mike > > > Terry Jeffrey wrote: > > > > Mike, > > > > A few specs on my 92YJ Jeep: > > > > - 35" tires > > - custom Dynatrac built D60 in both front and back > > - SUA with RE extreme-duty 4" lift springs > > - Confer 1" lift shackles in front > > - 1/2" MORE lift shackles in the back (levels it out nicely) > > - 1.25" JKS body lift > > - TJ flares > > - Hi-steer arms on the knuckles, tie rod mounted on the bottom > > - Adjustable JKS track bar. > > > > Total of 5 3/4 - 6.25" of lift (most suspension). When the front-end was > > built, they took all this info into consideration and I gave them several > > measurements (running width of existing drive axle, spring pads distance, > > etc, etc). Not to say the caster could still be off, though. This > > front-end has about 3000 miles on it, and no problems at all with this > > configuration until I encountered the DW the other day. At first > > inspection, I found the track bar loose on the frame side mount. I had been > > considering taking it off anyway, so at the time I temporarily removed it > > just to see how the road handling would be. > > > > I installed the front-end and track bar, springs, etc. No shop involved > > here. I got the aftermarket track bar to replace the original and have been > > using it for, oh, 6 years or so. Never a problem with it. Why a track bar? > > Because the YJ came with one originally. The spring company nor the > > Dynatrac recommended a track bar. If fact, Dynatrac suggested removing it. > > > > More than one person has advised me that I don't need the track bar, but I > > will be putting it back on anyway. Even though it may mask the real cause > > of the DW, I still take comfort in it being there! It is aligned in perfect > > angle with the drag link. I'll know this week if the caster is off and > > needs a shim or two. My guess is that's got to be the real problem, but > > we'll see. > > > > I bought this old Jeep new in late '91 and she now has over 203,000 miles on > > her and still runs great with original 4.0L and tranny. > > > > Thanks again Mike. Hey, I didn't mean to come across as a wise-a** last > > post to you. Some thought I sounded that way. > > > > Terry. > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > news:40391BF7.72A9DD6C@sympatico.ca... > > > I wonder on the track bar. > > > > > > Please fill me in on what you have so I can at least play 'devil's > > > advocate' with all the info I can get.... ;-) > > > > > > A stock YJ with the soft flat leaf springs came with a track bar. > > > > > > The CJ's before it with stiffer arched springs didn't come with, nor do > > > they need a track bar, nor do the lift kits call for one. > > > > > > You have 35's and a Dana 60 in the front???? > > > > > > I would then think you might just have a lift of some sorts??? Does the > > > lift call for the track bar or is that something the shop added to make > > > up for a possible death wobble issue rather than re-make the spring > > > perches to get the caster right or to make up for a bad u-joint and axle > > > angle issue? > > > > > > Do you have tall shackles per chance that the axle builders didn't know > > > about. That can crap out the caster big time. > > > > > > Mike > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > Thanks Mike. You might be right in that the caster wasn't set correctly > > > > when built. I certainly intend to find out this week. Being built by > > > > Dynatrac, though, it's hard to believe it isn't right. But one way to > > find > > > > out - get it checked. > > > > > > > > About the track bar and steering stabilizer. It's amazing how one hears > > so > > > > many conflicting suggestions from other Jeeping individuals and > > mechanics. > > > > But I realize what works or eliminates a problem for one might not > > > > necessarily be the solution for another. Along with you and another > > > > experienced Jeeping fellow I know and trust says without a doubt, put > > the > > > > track bar back on, which I intend to do today. One thing for sure - I > > > > didn't experience the DW until I discovered the track bar was loose on > > the > > > > frame side mount. Instead of removing the loose track bar and zeroing > > in on > > > > the stabilizer and/or caster as the culprit, my first (and easiest) DW > > > > "test" probably should have been to tighten the track bar back up and go > > hit > > > > that same bumpy road again to see if the DW was gone. I'll comment in > > the > > > > thread how this test goes this evening (only if I get around to doing it > > > > today -- I busted up my left hand some working on the house yesterday, > > and > > > > swollen like it is at the moment isn't feeling up to the task!). > > > > > > > > Thank again. I appreciate your insight and knowledge. > > > > > > > > Terry. > > > > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > > > news:4038D1A5.86262FC0@sympatico.ca... > > > > > When I see one thing wrong on a 'professionally' or backyard built > > item, > > > > > that implies the rest is shaky at best. > > > > > > > > > > Death wobble doesn't just happen! > > > > > > > > > > Something is either broken or not built correctly. > > > > > > > > > > You say nothing is broken, then that only leaves me with one other > > > > > conclusion, it is built wrong. > > > > > > > > > > I mean really. That is far more than just a 'guess'. > > > > > > > > > > Mike > > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > > > > > No, you are guessing. The front end is professionally built by > > > > Dynatrac. > > > > > > Everything is tight and fits correctly. I'm betting the caster is > > > > alright, > > > > > > but will get it checked anyway. I've also known quite a few people > > who > > > > have > > > > > > placed the steering stabilizer onto the drag link just like I have > > it. > > > > The > > > > > > reason it is on the drag link is because real estate is tight up > > front > > > > with > > > > > > the D60 and placing it on the tie rod initially interfered with the > > > > track > > > > > > bar. The track bar is going back on today. > > > > > > > > > > > > If you have a question about my rig, feel free to ask me about it. > > I've > > > > > > been Jeeping for many years and don't guess or take short cuts when > > it > > > > comes > > > > > > to my rig. > > > > > > > > > > > > Regards, > > > > > > Terry. > > > <snip> |
Re: A case of death wobble today
Mike, please consider a more optimistic outlook on things, my friend. ;-)
Life's too short to not be. Terry. "Mike Romain" <romainm@sympatico.ca> wrote in message news:40393109.59C41E4B@sympatico.ca... > Ok, so you have a custom, built all to crap unit, eh.... > > I have one pretty easy check 'maybe' for you... > > On a stock Jeep front end, the pinion face is straight up and down. > > So the proper caster angle corresponds to a straight up and down pinion. > > Mike > > > Terry Jeffrey wrote: > > > > Mike, > > > > A few specs on my 92YJ Jeep: > > > > - 35" tires > > - custom Dynatrac built D60 in both front and back > > - SUA with RE extreme-duty 4" lift springs > > - Confer 1" lift shackles in front > > - 1/2" MORE lift shackles in the back (levels it out nicely) > > - 1.25" JKS body lift > > - TJ flares > > - Hi-steer arms on the knuckles, tie rod mounted on the bottom > > - Adjustable JKS track bar. > > > > Total of 5 3/4 - 6.25" of lift (most suspension). When the front-end was > > built, they took all this info into consideration and I gave them several > > measurements (running width of existing drive axle, spring pads distance, > > etc, etc). Not to say the caster could still be off, though. This > > front-end has about 3000 miles on it, and no problems at all with this > > configuration until I encountered the DW the other day. At first > > inspection, I found the track bar loose on the frame side mount. I had been > > considering taking it off anyway, so at the time I temporarily removed it > > just to see how the road handling would be. > > > > I installed the front-end and track bar, springs, etc. No shop involved > > here. I got the aftermarket track bar to replace the original and have been > > using it for, oh, 6 years or so. Never a problem with it. Why a track bar? > > Because the YJ came with one originally. The spring company nor the > > Dynatrac recommended a track bar. If fact, Dynatrac suggested removing it. > > > > More than one person has advised me that I don't need the track bar, but I > > will be putting it back on anyway. Even though it may mask the real cause > > of the DW, I still take comfort in it being there! It is aligned in perfect > > angle with the drag link. I'll know this week if the caster is off and > > needs a shim or two. My guess is that's got to be the real problem, but > > we'll see. > > > > I bought this old Jeep new in late '91 and she now has over 203,000 miles on > > her and still runs great with original 4.0L and tranny. > > > > Thanks again Mike. Hey, I didn't mean to come across as a wise-a** last > > post to you. Some thought I sounded that way. > > > > Terry. > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > news:40391BF7.72A9DD6C@sympatico.ca... > > > I wonder on the track bar. > > > > > > Please fill me in on what you have so I can at least play 'devil's > > > advocate' with all the info I can get.... ;-) > > > > > > A stock YJ with the soft flat leaf springs came with a track bar. > > > > > > The CJ's before it with stiffer arched springs didn't come with, nor do > > > they need a track bar, nor do the lift kits call for one. > > > > > > You have 35's and a Dana 60 in the front???? > > > > > > I would then think you might just have a lift of some sorts??? Does the > > > lift call for the track bar or is that something the shop added to make > > > up for a possible death wobble issue rather than re-make the spring > > > perches to get the caster right or to make up for a bad u-joint and axle > > > angle issue? > > > > > > Do you have tall shackles per chance that the axle builders didn't know > > > about. That can crap out the caster big time. > > > > > > Mike > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > Thanks Mike. You might be right in that the caster wasn't set correctly > > > > when built. I certainly intend to find out this week. Being built by > > > > Dynatrac, though, it's hard to believe it isn't right. But one way to > > find > > > > out - get it checked. > > > > > > > > About the track bar and steering stabilizer. It's amazing how one hears > > so > > > > many conflicting suggestions from other Jeeping individuals and > > mechanics. > > > > But I realize what works or eliminates a problem for one might not > > > > necessarily be the solution for another. Along with you and another > > > > experienced Jeeping fellow I know and trust says without a doubt, put > > the > > > > track bar back on, which I intend to do today. One thing for sure - I > > > > didn't experience the DW until I discovered the track bar was loose on > > the > > > > frame side mount. Instead of removing the loose track bar and zeroing > > in on > > > > the stabilizer and/or caster as the culprit, my first (and easiest) DW > > > > "test" probably should have been to tighten the track bar back up and go > > hit > > > > that same bumpy road again to see if the DW was gone. I'll comment in > > the > > > > thread how this test goes this evening (only if I get around to doing it > > > > today -- I busted up my left hand some working on the house yesterday, > > and > > > > swollen like it is at the moment isn't feeling up to the task!). > > > > > > > > Thank again. I appreciate your insight and knowledge. > > > > > > > > Terry. > > > > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > > > news:4038D1A5.86262FC0@sympatico.ca... > > > > > When I see one thing wrong on a 'professionally' or backyard built > > item, > > > > > that implies the rest is shaky at best. > > > > > > > > > > Death wobble doesn't just happen! > > > > > > > > > > Something is either broken or not built correctly. > > > > > > > > > > You say nothing is broken, then that only leaves me with one other > > > > > conclusion, it is built wrong. > > > > > > > > > > I mean really. That is far more than just a 'guess'. > > > > > > > > > > Mike > > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > > > > > No, you are guessing. The front end is professionally built by > > > > Dynatrac. > > > > > > Everything is tight and fits correctly. I'm betting the caster is > > > > alright, > > > > > > but will get it checked anyway. I've also known quite a few people > > who > > > > have > > > > > > placed the steering stabilizer onto the drag link just like I have > > it. > > > > The > > > > > > reason it is on the drag link is because real estate is tight up > > front > > > > with > > > > > > the D60 and placing it on the tie rod initially interfered with the > > > > track > > > > > > bar. The track bar is going back on today. > > > > > > > > > > > > If you have a question about my rig, feel free to ask me about it. > > I've > > > > > > been Jeeping for many years and don't guess or take short cuts when > > it > > > > comes > > > > > > to my rig. > > > > > > > > > > > > Regards, > > > > > > Terry. > > > <snip> |
Re: A case of death wobble today
Mike, please consider a more optimistic outlook on things, my friend. ;-)
Life's too short to not be. Terry. "Mike Romain" <romainm@sympatico.ca> wrote in message news:40393109.59C41E4B@sympatico.ca... > Ok, so you have a custom, built all to crap unit, eh.... > > I have one pretty easy check 'maybe' for you... > > On a stock Jeep front end, the pinion face is straight up and down. > > So the proper caster angle corresponds to a straight up and down pinion. > > Mike > > > Terry Jeffrey wrote: > > > > Mike, > > > > A few specs on my 92YJ Jeep: > > > > - 35" tires > > - custom Dynatrac built D60 in both front and back > > - SUA with RE extreme-duty 4" lift springs > > - Confer 1" lift shackles in front > > - 1/2" MORE lift shackles in the back (levels it out nicely) > > - 1.25" JKS body lift > > - TJ flares > > - Hi-steer arms on the knuckles, tie rod mounted on the bottom > > - Adjustable JKS track bar. > > > > Total of 5 3/4 - 6.25" of lift (most suspension). When the front-end was > > built, they took all this info into consideration and I gave them several > > measurements (running width of existing drive axle, spring pads distance, > > etc, etc). Not to say the caster could still be off, though. This > > front-end has about 3000 miles on it, and no problems at all with this > > configuration until I encountered the DW the other day. At first > > inspection, I found the track bar loose on the frame side mount. I had been > > considering taking it off anyway, so at the time I temporarily removed it > > just to see how the road handling would be. > > > > I installed the front-end and track bar, springs, etc. No shop involved > > here. I got the aftermarket track bar to replace the original and have been > > using it for, oh, 6 years or so. Never a problem with it. Why a track bar? > > Because the YJ came with one originally. The spring company nor the > > Dynatrac recommended a track bar. If fact, Dynatrac suggested removing it. > > > > More than one person has advised me that I don't need the track bar, but I > > will be putting it back on anyway. Even though it may mask the real cause > > of the DW, I still take comfort in it being there! It is aligned in perfect > > angle with the drag link. I'll know this week if the caster is off and > > needs a shim or two. My guess is that's got to be the real problem, but > > we'll see. > > > > I bought this old Jeep new in late '91 and she now has over 203,000 miles on > > her and still runs great with original 4.0L and tranny. > > > > Thanks again Mike. Hey, I didn't mean to come across as a wise-a** last > > post to you. Some thought I sounded that way. > > > > Terry. > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > news:40391BF7.72A9DD6C@sympatico.ca... > > > I wonder on the track bar. > > > > > > Please fill me in on what you have so I can at least play 'devil's > > > advocate' with all the info I can get.... ;-) > > > > > > A stock YJ with the soft flat leaf springs came with a track bar. > > > > > > The CJ's before it with stiffer arched springs didn't come with, nor do > > > they need a track bar, nor do the lift kits call for one. > > > > > > You have 35's and a Dana 60 in the front???? > > > > > > I would then think you might just have a lift of some sorts??? Does the > > > lift call for the track bar or is that something the shop added to make > > > up for a possible death wobble issue rather than re-make the spring > > > perches to get the caster right or to make up for a bad u-joint and axle > > > angle issue? > > > > > > Do you have tall shackles per chance that the axle builders didn't know > > > about. That can crap out the caster big time. > > > > > > Mike > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > Thanks Mike. You might be right in that the caster wasn't set correctly > > > > when built. I certainly intend to find out this week. Being built by > > > > Dynatrac, though, it's hard to believe it isn't right. But one way to > > find > > > > out - get it checked. > > > > > > > > About the track bar and steering stabilizer. It's amazing how one hears > > so > > > > many conflicting suggestions from other Jeeping individuals and > > mechanics. > > > > But I realize what works or eliminates a problem for one might not > > > > necessarily be the solution for another. Along with you and another > > > > experienced Jeeping fellow I know and trust says without a doubt, put > > the > > > > track bar back on, which I intend to do today. One thing for sure - I > > > > didn't experience the DW until I discovered the track bar was loose on > > the > > > > frame side mount. Instead of removing the loose track bar and zeroing > > in on > > > > the stabilizer and/or caster as the culprit, my first (and easiest) DW > > > > "test" probably should have been to tighten the track bar back up and go > > hit > > > > that same bumpy road again to see if the DW was gone. I'll comment in > > the > > > > thread how this test goes this evening (only if I get around to doing it > > > > today -- I busted up my left hand some working on the house yesterday, > > and > > > > swollen like it is at the moment isn't feeling up to the task!). > > > > > > > > Thank again. I appreciate your insight and knowledge. > > > > > > > > Terry. > > > > > > > > "Mike Romain" <romainm@sympatico.ca> wrote in message > > > > news:4038D1A5.86262FC0@sympatico.ca... > > > > > When I see one thing wrong on a 'professionally' or backyard built > > item, > > > > > that implies the rest is shaky at best. > > > > > > > > > > Death wobble doesn't just happen! > > > > > > > > > > Something is either broken or not built correctly. > > > > > > > > > > You say nothing is broken, then that only leaves me with one other > > > > > conclusion, it is built wrong. > > > > > > > > > > I mean really. That is far more than just a 'guess'. > > > > > > > > > > Mike > > > > > > > > > > Terry Jeffrey wrote: > > > > > > > > > > > > No, you are guessing. The front end is professionally built by > > > > Dynatrac. > > > > > > Everything is tight and fits correctly. I'm betting the caster is > > > > alright, > > > > > > but will get it checked anyway. I've also known quite a few people > > who > > > > have > > > > > > placed the steering stabilizer onto the drag link just like I have > > it. > > > > The > > > > > > reason it is on the drag link is because real estate is tight up > > front > > > > with > > > > > > the D60 and placing it on the tie rod initially interfered with the > > > > track > > > > > > bar. The track bar is going back on today. > > > > > > > > > > > > If you have a question about my rig, feel free to ask me about it. > > I've > > > > > > been Jeeping for many years and don't guess or take short cuts when > > it > > > > comes > > > > > > to my rig. > > > > > > > > > > > > Regards, > > > > > > Terry. > > > <snip> |
Re: A case of death wobble today
No need for the arguing.
Here's the scoop so far: 1) Caster set at 6 degrees positive, which is Ok, 2) My right front lost two wheel weights (6ozs), not Ok, 3) My toe-in (which I set myself) was at 3/16"; he adjusted to 1/16", 4) Front tires are worn which I plan to rotate to the back, 5) Mechanic fella thought the steering stabilizer was too soft and might be shot. He suggested replacing it (he's also the 2nd mechanic that suggested ditching the track bar). I haven't tested it out yet on that same stretch of bumpy road, but might tonight. Or I might wait until I get the new stabilizer on. If it is gone, the DW was probably caused by a combination of these items. Thanks again for all the helpful comments and suggestions. Terry 92YJ "Roy J" <spamless@microsoft.net> wrote in message news:1Yf_b.131$pT1.86178@news.uswest.net... Since this seems to be the argument of the week, I went off and did some calculations. Sigh. I hate being an engineer. A while back there was a guy from the east coast, helicopter pilot, etc that had a built TJ (sorry I can't pull up his name) and we got into the discussion of DW on the TJ. He finally convinced me that big tires need LESS caster than stock tires (say about 5 degrees) rather than the 6 to 7 degrees on the various shop specs. And that the toe in on big tires needs to be as close to zero as you can get and still be toe in. The OP stated that he has the 1" lift Confer shackles (that are 2" longer than stock) Sin (2"/45") is 2.56 degrees. So the OP is shorting himself 2.5 degrees on the caster (unless he has added the appropriate shims of course) Every inch lowering in the front shaves another .6 degree off the caster. So if he hits the brakes and gets 3" of front dive, he shaves another 2 degrees off the caster. If he has any permamanet spring wrap, he will shave off some more. (35" tires and a D60 probably means he pushes it a little!) The OP stated that he has high mileage on his 35" tires. Most of us have not solved the problem of perfect wear on big tires so I'll assume that they are not worn evenly. He did not state if he had balanced them lately but even then, did he shuck a wheel weight? The OP has the reversed tie rod , this changes things from what most of us run. Th OP told Dynatrac about his vehicle, did he indicate he was going to use the Confer shackles? And does Dynatrac set up the axle for a specified caster angle??? Ie do they do factory stock or what works?? When we tackle a harmonic vibration problem (and this is a special case of the general theory) we have 4 basic methods to deal with things: 1) change the freqeuency of the system 2) "Stiffen" the system to move the harmonic up higher. 3) Dampen the system 4) Reduce the input energy at the vibration frequency to keep if from going off. In a Jeep, #1 is tough, it has to move through a range of frequencies (speeds) #2 involves tightening up the slop in the system (tie rod ends, ball joints, heavier tie rod, etc) Plus you need enough toe in to keep the system preloaded one direction. #3 is the infamous steering stabilzer. #4 is mostly from the tires. They need to be dynamicly balanced at the frequency in question (about 60 mph) AND they need to be round and straight. Keep in mind that 35" tires run almost 100 pounds a piece, I have seen them worn down with up to 1/4" cups and waves in them. Lots of side energy available here. Net: I'll sit here and speculate that the actual caster is way less than the OP thinks it is, that the tires are worn and out of balance (not a lot but enough!), that he hit the brakes and a bump with a bit of a turn, the whole works started to shake, and the steering stabilzer was not up to the job of getting control back. Take your choice of fixes, I personally prefer naturally stable systems to ones that are subject to failure from the fatigue of a single component. Cheers. CRWLR wrote: > Think of how the forks on a motorcycle are raked. A chopper goes straighat > ahead really good, but can be a bitch to turn, and a racing bike can turn on > a dime, but the steering is very twitchy. The most significant difference in > these examples is the rake of the forks, and this rake is similar to the > Caster angle. > > As I said earlier, caster typically does not play a large role in the > adjustments of the front end geometry because it is pretty much set during > manufacturing of the axle. The spring perches define the caster angle. > Assuming the axle is the right one, the caster angle should be right. Of > course, with custom modifications - lift - the caster angle can change > enough to become a player in DW. > > Caster angle is the imaginary line through the upper and lower ball joints, > and the center of the spindle. Properly set, the caster angle should be > about 7° towards the rear of the vehicle. That is, the upper ball joint > should trail the lower by about 7°. Perhaps the number is a little bit > different in your case, but greater angles will be more stable than lesser > angles. When the angle drops to about 4° or less, then the tires will search > for the straight ahead position, and this sets up the DW symptoms. There is > an easy test for Caster angle ... Go to an open area and make a Uturn, or a > manuver that simulates what you might do when backing from a parking stall. > Turn the steering wheel fully to one stop, then begin going and see if the > wheel returns to center on its own, or if it remains in Turning Mode and > requires you to physically turn back to center. If you have to drive it back > to straight ahead, then your caster is not great enough, but if it wants to > go to center on its own, then the caster is probably OK. > > In my motorcycle analogy, there are other geometry forces at play, so the > analogy breaks down pretty quickly, but in general terms, it works pretty > well. I am certain that my analogy will be corrected, but it works for now. > > My FSM says the spec for Caster angle is 6°. > > > > > > "Terry Jeffrey" <twjeffrey@hotmail.com> wrote in message > news:a5SZb.4126$aT1.454@newsread1.news.pas.earthli nk.net... > >>The ball joints appear to be good. I did the push-pull-raised-tire test > > and > >>it checked out Ok. All the rod ends are tight and lubed. I'll get the >>caster checked out next week. Explain, if you will, why caster would be a >>player in DW. This could be my problem. If the caster angle is off, >>wouldn't this only cause the vehicle to pull to one side or the other? >> >>It was suggested to move the steering stabilizer from the drag link to the >>tie rod. When I did this, I still got the same DW. I thought I felt a >>little air in the stabilizer at the extended end while testing it, and > > will > >>replace it as soon as I can find one. >> >>Your track bar comment is noted. I'd like to leave it off all together >>because real estate up front is a premium right now with the Dana60. But >>will put it back on nice and tight and put the DW to the test again. >> >>Thanks again, >>Terry. >> >> >> >> >>"CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message >>news:103foc9kj445236@corp.supernews.com... >> >>>If all of that stuff is new, I would not think the steering stabalizer >> >>would >> >>>be so significant. Did you attempt the tests that I described? (If I >>>described something incorrectly, did you try what might have been >> >>suggested >> >>>to correct me?) >>> >>>If you suspect the track bar is worn, and causing a problem with >> >>looseness, >> >>>then removing the trackbar altogether is not much of a confirmation > > test. > >>If >> >>>yo had no trackbar, and complained of DW, then put the bar on to see if >> >>the >> >>>DW went away, then you would have a reasonable diagnostic test. Taking > > the > >>>trackbar off is the same thing as having one on that had worn bushings. >>> |
Re: A case of death wobble today
No need for the arguing.
Here's the scoop so far: 1) Caster set at 6 degrees positive, which is Ok, 2) My right front lost two wheel weights (6ozs), not Ok, 3) My toe-in (which I set myself) was at 3/16"; he adjusted to 1/16", 4) Front tires are worn which I plan to rotate to the back, 5) Mechanic fella thought the steering stabilizer was too soft and might be shot. He suggested replacing it (he's also the 2nd mechanic that suggested ditching the track bar). I haven't tested it out yet on that same stretch of bumpy road, but might tonight. Or I might wait until I get the new stabilizer on. If it is gone, the DW was probably caused by a combination of these items. Thanks again for all the helpful comments and suggestions. Terry 92YJ "Roy J" <spamless@microsoft.net> wrote in message news:1Yf_b.131$pT1.86178@news.uswest.net... Since this seems to be the argument of the week, I went off and did some calculations. Sigh. I hate being an engineer. A while back there was a guy from the east coast, helicopter pilot, etc that had a built TJ (sorry I can't pull up his name) and we got into the discussion of DW on the TJ. He finally convinced me that big tires need LESS caster than stock tires (say about 5 degrees) rather than the 6 to 7 degrees on the various shop specs. And that the toe in on big tires needs to be as close to zero as you can get and still be toe in. The OP stated that he has the 1" lift Confer shackles (that are 2" longer than stock) Sin (2"/45") is 2.56 degrees. So the OP is shorting himself 2.5 degrees on the caster (unless he has added the appropriate shims of course) Every inch lowering in the front shaves another .6 degree off the caster. So if he hits the brakes and gets 3" of front dive, he shaves another 2 degrees off the caster. If he has any permamanet spring wrap, he will shave off some more. (35" tires and a D60 probably means he pushes it a little!) The OP stated that he has high mileage on his 35" tires. Most of us have not solved the problem of perfect wear on big tires so I'll assume that they are not worn evenly. He did not state if he had balanced them lately but even then, did he shuck a wheel weight? The OP has the reversed tie rod , this changes things from what most of us run. Th OP told Dynatrac about his vehicle, did he indicate he was going to use the Confer shackles? And does Dynatrac set up the axle for a specified caster angle??? Ie do they do factory stock or what works?? When we tackle a harmonic vibration problem (and this is a special case of the general theory) we have 4 basic methods to deal with things: 1) change the freqeuency of the system 2) "Stiffen" the system to move the harmonic up higher. 3) Dampen the system 4) Reduce the input energy at the vibration frequency to keep if from going off. In a Jeep, #1 is tough, it has to move through a range of frequencies (speeds) #2 involves tightening up the slop in the system (tie rod ends, ball joints, heavier tie rod, etc) Plus you need enough toe in to keep the system preloaded one direction. #3 is the infamous steering stabilzer. #4 is mostly from the tires. They need to be dynamicly balanced at the frequency in question (about 60 mph) AND they need to be round and straight. Keep in mind that 35" tires run almost 100 pounds a piece, I have seen them worn down with up to 1/4" cups and waves in them. Lots of side energy available here. Net: I'll sit here and speculate that the actual caster is way less than the OP thinks it is, that the tires are worn and out of balance (not a lot but enough!), that he hit the brakes and a bump with a bit of a turn, the whole works started to shake, and the steering stabilzer was not up to the job of getting control back. Take your choice of fixes, I personally prefer naturally stable systems to ones that are subject to failure from the fatigue of a single component. Cheers. CRWLR wrote: > Think of how the forks on a motorcycle are raked. A chopper goes straighat > ahead really good, but can be a bitch to turn, and a racing bike can turn on > a dime, but the steering is very twitchy. The most significant difference in > these examples is the rake of the forks, and this rake is similar to the > Caster angle. > > As I said earlier, caster typically does not play a large role in the > adjustments of the front end geometry because it is pretty much set during > manufacturing of the axle. The spring perches define the caster angle. > Assuming the axle is the right one, the caster angle should be right. Of > course, with custom modifications - lift - the caster angle can change > enough to become a player in DW. > > Caster angle is the imaginary line through the upper and lower ball joints, > and the center of the spindle. Properly set, the caster angle should be > about 7° towards the rear of the vehicle. That is, the upper ball joint > should trail the lower by about 7°. Perhaps the number is a little bit > different in your case, but greater angles will be more stable than lesser > angles. When the angle drops to about 4° or less, then the tires will search > for the straight ahead position, and this sets up the DW symptoms. There is > an easy test for Caster angle ... Go to an open area and make a Uturn, or a > manuver that simulates what you might do when backing from a parking stall. > Turn the steering wheel fully to one stop, then begin going and see if the > wheel returns to center on its own, or if it remains in Turning Mode and > requires you to physically turn back to center. If you have to drive it back > to straight ahead, then your caster is not great enough, but if it wants to > go to center on its own, then the caster is probably OK. > > In my motorcycle analogy, there are other geometry forces at play, so the > analogy breaks down pretty quickly, but in general terms, it works pretty > well. I am certain that my analogy will be corrected, but it works for now. > > My FSM says the spec for Caster angle is 6°. > > > > > > "Terry Jeffrey" <twjeffrey@hotmail.com> wrote in message > news:a5SZb.4126$aT1.454@newsread1.news.pas.earthli nk.net... > >>The ball joints appear to be good. I did the push-pull-raised-tire test > > and > >>it checked out Ok. All the rod ends are tight and lubed. I'll get the >>caster checked out next week. Explain, if you will, why caster would be a >>player in DW. This could be my problem. If the caster angle is off, >>wouldn't this only cause the vehicle to pull to one side or the other? >> >>It was suggested to move the steering stabilizer from the drag link to the >>tie rod. When I did this, I still got the same DW. I thought I felt a >>little air in the stabilizer at the extended end while testing it, and > > will > >>replace it as soon as I can find one. >> >>Your track bar comment is noted. I'd like to leave it off all together >>because real estate up front is a premium right now with the Dana60. But >>will put it back on nice and tight and put the DW to the test again. >> >>Thanks again, >>Terry. >> >> >> >> >>"CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message >>news:103foc9kj445236@corp.supernews.com... >> >>>If all of that stuff is new, I would not think the steering stabalizer >> >>would >> >>>be so significant. Did you attempt the tests that I described? (If I >>>described something incorrectly, did you try what might have been >> >>suggested >> >>>to correct me?) >>> >>>If you suspect the track bar is worn, and causing a problem with >> >>looseness, >> >>>then removing the trackbar altogether is not much of a confirmation > > test. > >>If >> >>>yo had no trackbar, and complained of DW, then put the bar on to see if >> >>the >> >>>DW went away, then you would have a reasonable diagnostic test. Taking > > the > >>>trackbar off is the same thing as having one on that had worn bushings. >>> |
Re: A case of death wobble today
No need for the arguing.
Here's the scoop so far: 1) Caster set at 6 degrees positive, which is Ok, 2) My right front lost two wheel weights (6ozs), not Ok, 3) My toe-in (which I set myself) was at 3/16"; he adjusted to 1/16", 4) Front tires are worn which I plan to rotate to the back, 5) Mechanic fella thought the steering stabilizer was too soft and might be shot. He suggested replacing it (he's also the 2nd mechanic that suggested ditching the track bar). I haven't tested it out yet on that same stretch of bumpy road, but might tonight. Or I might wait until I get the new stabilizer on. If it is gone, the DW was probably caused by a combination of these items. Thanks again for all the helpful comments and suggestions. Terry 92YJ "Roy J" <spamless@microsoft.net> wrote in message news:1Yf_b.131$pT1.86178@news.uswest.net... Since this seems to be the argument of the week, I went off and did some calculations. Sigh. I hate being an engineer. A while back there was a guy from the east coast, helicopter pilot, etc that had a built TJ (sorry I can't pull up his name) and we got into the discussion of DW on the TJ. He finally convinced me that big tires need LESS caster than stock tires (say about 5 degrees) rather than the 6 to 7 degrees on the various shop specs. And that the toe in on big tires needs to be as close to zero as you can get and still be toe in. The OP stated that he has the 1" lift Confer shackles (that are 2" longer than stock) Sin (2"/45") is 2.56 degrees. So the OP is shorting himself 2.5 degrees on the caster (unless he has added the appropriate shims of course) Every inch lowering in the front shaves another .6 degree off the caster. So if he hits the brakes and gets 3" of front dive, he shaves another 2 degrees off the caster. If he has any permamanet spring wrap, he will shave off some more. (35" tires and a D60 probably means he pushes it a little!) The OP stated that he has high mileage on his 35" tires. Most of us have not solved the problem of perfect wear on big tires so I'll assume that they are not worn evenly. He did not state if he had balanced them lately but even then, did he shuck a wheel weight? The OP has the reversed tie rod , this changes things from what most of us run. Th OP told Dynatrac about his vehicle, did he indicate he was going to use the Confer shackles? And does Dynatrac set up the axle for a specified caster angle??? Ie do they do factory stock or what works?? When we tackle a harmonic vibration problem (and this is a special case of the general theory) we have 4 basic methods to deal with things: 1) change the freqeuency of the system 2) "Stiffen" the system to move the harmonic up higher. 3) Dampen the system 4) Reduce the input energy at the vibration frequency to keep if from going off. In a Jeep, #1 is tough, it has to move through a range of frequencies (speeds) #2 involves tightening up the slop in the system (tie rod ends, ball joints, heavier tie rod, etc) Plus you need enough toe in to keep the system preloaded one direction. #3 is the infamous steering stabilzer. #4 is mostly from the tires. They need to be dynamicly balanced at the frequency in question (about 60 mph) AND they need to be round and straight. Keep in mind that 35" tires run almost 100 pounds a piece, I have seen them worn down with up to 1/4" cups and waves in them. Lots of side energy available here. Net: I'll sit here and speculate that the actual caster is way less than the OP thinks it is, that the tires are worn and out of balance (not a lot but enough!), that he hit the brakes and a bump with a bit of a turn, the whole works started to shake, and the steering stabilzer was not up to the job of getting control back. Take your choice of fixes, I personally prefer naturally stable systems to ones that are subject to failure from the fatigue of a single component. Cheers. CRWLR wrote: > Think of how the forks on a motorcycle are raked. A chopper goes straighat > ahead really good, but can be a bitch to turn, and a racing bike can turn on > a dime, but the steering is very twitchy. The most significant difference in > these examples is the rake of the forks, and this rake is similar to the > Caster angle. > > As I said earlier, caster typically does not play a large role in the > adjustments of the front end geometry because it is pretty much set during > manufacturing of the axle. The spring perches define the caster angle. > Assuming the axle is the right one, the caster angle should be right. Of > course, with custom modifications - lift - the caster angle can change > enough to become a player in DW. > > Caster angle is the imaginary line through the upper and lower ball joints, > and the center of the spindle. Properly set, the caster angle should be > about 7° towards the rear of the vehicle. That is, the upper ball joint > should trail the lower by about 7°. Perhaps the number is a little bit > different in your case, but greater angles will be more stable than lesser > angles. When the angle drops to about 4° or less, then the tires will search > for the straight ahead position, and this sets up the DW symptoms. There is > an easy test for Caster angle ... Go to an open area and make a Uturn, or a > manuver that simulates what you might do when backing from a parking stall. > Turn the steering wheel fully to one stop, then begin going and see if the > wheel returns to center on its own, or if it remains in Turning Mode and > requires you to physically turn back to center. If you have to drive it back > to straight ahead, then your caster is not great enough, but if it wants to > go to center on its own, then the caster is probably OK. > > In my motorcycle analogy, there are other geometry forces at play, so the > analogy breaks down pretty quickly, but in general terms, it works pretty > well. I am certain that my analogy will be corrected, but it works for now. > > My FSM says the spec for Caster angle is 6°. > > > > > > "Terry Jeffrey" <twjeffrey@hotmail.com> wrote in message > news:a5SZb.4126$aT1.454@newsread1.news.pas.earthli nk.net... > >>The ball joints appear to be good. I did the push-pull-raised-tire test > > and > >>it checked out Ok. All the rod ends are tight and lubed. I'll get the >>caster checked out next week. Explain, if you will, why caster would be a >>player in DW. This could be my problem. If the caster angle is off, >>wouldn't this only cause the vehicle to pull to one side or the other? >> >>It was suggested to move the steering stabilizer from the drag link to the >>tie rod. When I did this, I still got the same DW. I thought I felt a >>little air in the stabilizer at the extended end while testing it, and > > will > >>replace it as soon as I can find one. >> >>Your track bar comment is noted. I'd like to leave it off all together >>because real estate up front is a premium right now with the Dana60. But >>will put it back on nice and tight and put the DW to the test again. >> >>Thanks again, >>Terry. >> >> >> >> >>"CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message >>news:103foc9kj445236@corp.supernews.com... >> >>>If all of that stuff is new, I would not think the steering stabalizer >> >>would >> >>>be so significant. Did you attempt the tests that I described? (If I >>>described something incorrectly, did you try what might have been >> >>suggested >> >>>to correct me?) >>> >>>If you suspect the track bar is worn, and causing a problem with >> >>looseness, >> >>>then removing the trackbar altogether is not much of a confirmation > > test. > >>If >> >>>yo had no trackbar, and complained of DW, then put the bar on to see if >> >>the >> >>>DW went away, then you would have a reasonable diagnostic test. Taking > > the > >>>trackbar off is the same thing as having one on that had worn bushings. >>> |
Re: A case of death wobble today
Come again?
L.W.(ßill) ------ III wrote: > Except putting a longer shackle on increases it's leverage on the > spring, almost instantly pulling the arc out of the spring, for no > change. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > Old Crow wrote: > >>They would be if some of the height is gained by using the lift >>shackles. I was looking at these as a cheap way to lift my YJ, but it >>didn't take an engineer to tell me that lifing one end of the springs >>is going to rotate the axle and thus change the castor angles. >> >>-- >>Old Crow >>'82 Shovelhead FLT 92" 'Pearl' >>'95 Jeep YJ Rio Grande >>ASE Certified Master Auto Tech + L1 >>TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
Re: A case of death wobble today
Come again?
L.W.(ßill) ------ III wrote: > Except putting a longer shackle on increases it's leverage on the > spring, almost instantly pulling the arc out of the spring, for no > change. > God Bless America, ßill O|||||||O > mailto:-------------------- http://www.----------.com/ > > Old Crow wrote: > >>They would be if some of the height is gained by using the lift >>shackles. I was looking at these as a cheap way to lift my YJ, but it >>didn't take an engineer to tell me that lifing one end of the springs >>is going to rotate the axle and thus change the castor angles. >> >>-- >>Old Crow >>'82 Shovelhead FLT 92" 'Pearl' >>'95 Jeep YJ Rio Grande >>ASE Certified Master Auto Tech + L1 >>TOMKAT, BS#133, SENS, MAMBM, DOF#51 |
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