My 03 tj sport manuel tranny, has this thump (only once) when I take off from a stop, its sounds like its coming from the right side sometimes the front n others times the rear, also when I put it into reverse I hear the same thump.I put it in 4 wd and hear it in moving frontwards only not in reverse. If I play with it and give a little gas ease up and give again I can hear the thump each time I press to fuel again. I have check for loose wheel, my univ joints on the wheel look okay and so as them on the driveshafts, tried to check the bolts on the transfer case seem tight. Its annoying not knowing what it is.
Any one got a clue? Tks

 

Did you check the rear controle arms for warnout bushings? My 97 TJ had that .

 

I had the idea it was the front/rear control arms bushings as with my old 89 xj I had the same sound and whenever I retightened the bolts on the control arms it would go away for awhile, then come back again. They are as tight as I can get them without using a bar. Well if ur diagnoses is the same as mine and another buddy then we won't worry about it anymore. And change the bushings in the near future. Thks for the reply.

 

Do you have stock arms or aftermaket ? I have rubicon express arms that need new rubber bushings at the frame mount . They seem to be hard to get.

 

Must be one of those days my head is in my back side. I meant to say the track bar (bushings). The bolt inside the bushing must have a sleeve the bolt passes thur and must have a little slack in it that makes the noise when it moves.
Control arms are okay changed the lowers ones when I did the 4" lift, so there all new and get greased regularly.
I'd try national4wd go to there website and give them a call they have a free toll number.

 

I had a thumping sound too and found it to be my rear shock,the bottom rubber was worn out,too me a while to find it,but that was my problem.

Dan

 

Thanks guys since I posted this the problem has stopped, exactly what I did to correct it I am not sure, I did tighten everything up from the lift job and changed the ball joints upper and lower at the pass front wheel so may be thats what it was..anyways thanks for your input

 

loosen it all up so you can pin point exactly what it was...

good to hear though, i've got a similar thump i've got to figure out myself...