No Bob, I just recently got the 31's last winter. I had my '98 since
winter of 97 and did these comparison of stock jeep vehicles.
3.07 w/ grizzlys vs. the 3.73 w/ 30" wheel package and Dana 44.

The 3.07 had way better mpg.

With the 30" wheel deal, the speedo was off from factory. That's how
it was back in '98. If you put BFG's 31" on, it's pretty much dead on
without changing a thing. Don't know how it is now.



magicclaw@mac.com (Bob) wrote in message news:<47b769ae.0409150544.7a9aeecf@posting.google. com>...
> When you switched to the 31s with your 3.73s (as I understood it you
> were running smaller tires on the 3.73 axles before), did you adjust
> your gas mileage comparison for the tire size difference? Because your
> speedo and therefore trip odo will be off slightly...enough to hide
> probably 2 or 3 mpg (depending on what your original tire size(s)
> were).
>
>
> budda66f@aol.com (Jeff) wrote in message news:<85392d89.0409140610.13a214eb@posting.google. com>...
> > "Jerry Bransford" <jerrypb@***.net> wrote in message news:<L7s0d.81286$yh.30792@fed1read05>...
> > > Jeff, it sure reads like you're reversing how a 3.73 vs. a 3.07 would be
> > > described by anyone I know.
> > >
> > > Jerry
> > > --
> > > Jerry Bransford
> > > PP-ASEL N6TAY
> > > See the Geezer Jeep at
> > > http://members.***.net/jerrypb/
> > > "Jeff" <budda66f@aol.com> wrote in message
> > >
> > Maybe I am Jerry. But I know the 3.07 had a lot of top end
> > left in fifth gear and it would fly on the highway. The 3.73's made
> > my jeep feel peppy at low speeds. I think this is how it's supposed
> > to work. Am I way off?
> >
> > Maybe the tire sizes had a lot to do with it as well. But my same
> > travel when I got my Dana 44/3.73 TJ required a lot more trips to the
> > gas station. I love it but it's a pig.
> >
> > The 3.07 had those grizzly wheels and metric tires. They weren't the
> > real small ones, the medium sized factory tires. P29 or something, I
> > can't remember. I calculated
> > mostly highway MPG as almost 21 mpg! For a six banger that's good

 

I just put 31's on my 2004 with the 3.73 and gas mileage dropped 1 mpg.
Speedo is off by a couple miles an hour, I checked it on one of those
roadside radar things

--
Tim

[____]
(OIIIIIIO)


"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0409150544.7a9aeecf@posting.google.c om...
> When you switched to the 31s with your 3.73s (as I understood it you
> were running smaller tires on the 3.73 axles before), did you adjust
> your gas mileage comparison for the tire size difference? Because your
> speedo and therefore trip odo will be off slightly...enough to hide
> probably 2 or 3 mpg (depending on what your original tire size(s)
> were).
>
>
> budda66f@aol.com (Jeff) wrote in message
> news:<85392d89.0409140610.13a214eb@posting.google. com>...
>> "Jerry Bransford" <jerrypb@***.net> wrote in message
>> news:<L7s0d.81286$yh.30792@fed1read05>...
>> > Jeff, it sure reads like you're reversing how a 3.73 vs. a 3.07 would
>> > be
>> > described by anyone I know.
>> >
>> > Jerry
>> > --
>> > Jerry Bransford
>> > PP-ASEL N6TAY
>> > See the Geezer Jeep at
>> > http://members.***.net/jerrypb/
>> > "Jeff" <budda66f@aol.com> wrote in message
>> >
>> Maybe I am Jerry. But I know the 3.07 had a lot of top end
>> left in fifth gear and it would fly on the highway. The 3.73's made
>> my jeep feel peppy at low speeds. I think this is how it's supposed
>> to work. Am I way off?
>>
>> Maybe the tire sizes had a lot to do with it as well. But my same
>> travel when I got my Dana 44/3.73 TJ required a lot more trips to the
>> gas station. I love it but it's a pig.
>>
>> The 3.07 had those grizzly wheels and metric tires. They weren't the
>> real small ones, the medium sized factory tires. P29 or something, I
>> can't remember. I calculated
>> mostly highway MPG as almost 21 mpg! For a six banger that's good

 

I just put 31's on my 2004 with the 3.73 and gas mileage dropped 1 mpg.
Speedo is off by a couple miles an hour, I checked it on one of those
roadside radar things

--
Tim

[____]
(OIIIIIIO)


"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0409150544.7a9aeecf@posting.google.c om...
> When you switched to the 31s with your 3.73s (as I understood it you
> were running smaller tires on the 3.73 axles before), did you adjust
> your gas mileage comparison for the tire size difference? Because your
> speedo and therefore trip odo will be off slightly...enough to hide
> probably 2 or 3 mpg (depending on what your original tire size(s)
> were).
>
>
> budda66f@aol.com (Jeff) wrote in message
> news:<85392d89.0409140610.13a214eb@posting.google. com>...
>> "Jerry Bransford" <jerrypb@***.net> wrote in message
>> news:<L7s0d.81286$yh.30792@fed1read05>...
>> > Jeff, it sure reads like you're reversing how a 3.73 vs. a 3.07 would
>> > be
>> > described by anyone I know.
>> >
>> > Jerry
>> > --
>> > Jerry Bransford
>> > PP-ASEL N6TAY
>> > See the Geezer Jeep at
>> > http://members.***.net/jerrypb/
>> > "Jeff" <budda66f@aol.com> wrote in message
>> >
>> Maybe I am Jerry. But I know the 3.07 had a lot of top end
>> left in fifth gear and it would fly on the highway. The 3.73's made
>> my jeep feel peppy at low speeds. I think this is how it's supposed
>> to work. Am I way off?
>>
>> Maybe the tire sizes had a lot to do with it as well. But my same
>> travel when I got my Dana 44/3.73 TJ required a lot more trips to the
>> gas station. I love it but it's a pig.
>>
>> The 3.07 had those grizzly wheels and metric tires. They weren't the
>> real small ones, the medium sized factory tires. P29 or something, I
>> can't remember. I calculated
>> mostly highway MPG as almost 21 mpg! For a six banger that's good

 

I just put 31's on my 2004 with the 3.73 and gas mileage dropped 1 mpg.
Speedo is off by a couple miles an hour, I checked it on one of those
roadside radar things

--
Tim

[____]
(OIIIIIIO)


"Bob" <magicclaw@mac.com> wrote in message
news:47b769ae.0409150544.7a9aeecf@posting.google.c om...
> When you switched to the 31s with your 3.73s (as I understood it you
> were running smaller tires on the 3.73 axles before), did you adjust
> your gas mileage comparison for the tire size difference? Because your
> speedo and therefore trip odo will be off slightly...enough to hide
> probably 2 or 3 mpg (depending on what your original tire size(s)
> were).
>
>
> budda66f@aol.com (Jeff) wrote in message
> news:<85392d89.0409140610.13a214eb@posting.google. com>...
>> "Jerry Bransford" <jerrypb@***.net> wrote in message
>> news:<L7s0d.81286$yh.30792@fed1read05>...
>> > Jeff, it sure reads like you're reversing how a 3.73 vs. a 3.07 would
>> > be
>> > described by anyone I know.
>> >
>> > Jerry
>> > --
>> > Jerry Bransford
>> > PP-ASEL N6TAY
>> > See the Geezer Jeep at
>> > http://members.***.net/jerrypb/
>> > "Jeff" <budda66f@aol.com> wrote in message
>> >
>> Maybe I am Jerry. But I know the 3.07 had a lot of top end
>> left in fifth gear and it would fly on the highway. The 3.73's made
>> my jeep feel peppy at low speeds. I think this is how it's supposed
>> to work. Am I way off?
>>
>> Maybe the tire sizes had a lot to do with it as well. But my same
>> travel when I got my Dana 44/3.73 TJ required a lot more trips to the
>> gas station. I love it but it's a pig.
>>
>> The 3.07 had those grizzly wheels and metric tires. They weren't the
>> real small ones, the medium sized factory tires. P29 or something, I
>> can't remember. I calculated
>> mostly highway MPG as almost 21 mpg! For a six banger that's good