clunk clunk clunk

[black2door]

hey, my 97 xj with a 4.0, AX-15, 8.25 rear and 140,000 miles is making a clunking sound when i let off the clutch or when im going and i let off the gas and then when i hit it again it clunks. Its coming from the rear and i think it could be my differential.
I already checked my ujoints and i changed my diff fluid and shocks yesterday

It clunked when I bought it about a month ago but i am just now getting to it, i wouldnt think so but is it normal.

I was hoping to lift it and put alot of stuff on it but didnt want to if it will only last me another year.

[90xj06]

it sounds like a cluch related problem. but are you sure its not the u-joints?

[black2door]

i think i guess ill just replace them and see if that helps

[Frank Z]

I just went through this exact same problem 2 days ago! Turns out it was my pinion angle, although the problem literally developed overnight. I confirmed the pinion angle diagnosis by putting the rear axle on Jackstands, loosened the u-bolts, and used my floor jack to raise the pinion up. Be carefull and make sure that the pinion yolk won't hit the floorjack. Start the engine, put it in gear and slowly increase the wheel speed and let off the gas. If the noise is no longer present, then you've found the problem.

I corrected my pinion angle using 6deg. shims from NAPA. This winter I'll yank them out and relocate the spring perches.

[CanMan]

hey, my 97 xj with a 4.0, AX-15, 8.25 rear and 140,000 miles is making a clunking sound when i let off the clutch or when im going and i let off the gas and then when i hit it again it clunks. Its coming from the rear and i think it could be my differential.

My old D35 had a clunking noise, before It got replaced. Found it was the rearend, having too much play in it. The pinion would turn almost an 1/8th before it would make contact again.

I already checked my ujoints and i changed my diff fluid and shocks yesterday.

If the u joints seem well, don't replace them, unless you or someone else knows for a fact they are junk.

It clunked when I bought it about a month ago but i am just now getting to it, i wouldnt think so but is it normal?

For a stock rig, or even a modified one, no. Its not going to ride and sound like a Cadillac, but no loud or big clunks from drivetrain should be normal.

I was hoping to lift it and put alot of stuff on it but didnt want to if it will only last me another year.

Lifting it, bigger tires, ect. ect. can cause breakage, and it sure won't last unless replaced, well taken care of, or serviced well.

[Frank Z]

Well?

[Lil Stinky]

I'm having the same problem with my 98 XJ. Mine is automatic but I get the clunk noise when shifting from reverse to drive. I can also feel it when I first take off from a light sometimes. My leaf springs seem to be flat and I'm thinking some new ones will correct the pinion angle.

[black2door]

I just went through this exact same problem 2 days ago! Turns out it was my pinion angle, although the problem literally developed overnight. I confirmed the pinion angle diagnosis by putting the rear axle on Jackstands, loosened the u-bolts, and used my floor jack to raise the pinion up. Be carefull and make sure that the pinion yolk won't hit the floorjack. Start the engine, put it in gear and slowly increase the wheel speed and let off the gas. If the noise is no longer present, then you've found the problem.

I corrected my pinion angle using 6deg. shims from NAPA. This winter I'll yank them out and relocate the spring perches.



I havent had time to mess with it but this weekend ill try that and see if its my problem.

ive also noticed my leaf springs look more like an S so if that doesnt work ill change

[rocklandxjer]

if you lift it and put bigger tires on it youll want to regear anyway, so if its your gears, theyl be fixed anyway

[black2door]

if you lift it and put bigger tires on it youll want to regear anyway, so if its your gears, theyl be fixed anyway

will i need to regear if i do a 3 inch lift and 31s

[CanMan]

Since you have a stick, you should have 3.07 gears. I had them with a stick too, 3.07's, and could not stand it anywhere. On the freeway it sucked, mostly driving in 4th to keep up speed. Take offs were crappy. Wheeling was worse, even in low range. I now run 4.56 gears, with the same 31's, and still wish they were a bit lower, like 4.88's or so. But having a Chrysler rear end, It doesn't go past 4.56. I love them now driving around, just higher RPM's on the freeway.


Read this: http://www.naxja.org/forum/showthread.php?t=46901&highlight=gearing (http://www.naxja.org/forum/showthread.php?t=46901&highlight=gearing)

[black2door]

so if i regear i just get the lower ring and pinion right. This is my first jeep and i get confused easily.

[CanMan]

so if i regear i just get the lower ring and pinion right. This is my first jeep and i get confused easily.

There is a little more to it than just buying a R&P, and slapping it in. They require proper setup and such. You can do it yourself, like many have, if you have the proper tools and knowledge of doing it. Usually an axle can run from $200(?) bucks plus per, to regear, depending on parts used/needed. You will need a new carrier for the front, if you go lower than 3.73 gears. The Chrysler rear is the same for all ratios. HTH. :cool:

[matt25]

I'm having the same problem with my 98 XJ. Mine is automatic but I get the clunk noise when shifting from reverse to drive. I can also feel it when I first take off from a light sometimes. My leaf springs seem to be flat and I'm thinking some new ones will correct the pinion angle. i had a similar problem on my 94 xj as you are having turned out that my flywheel to torque converter bolts where loose. you may want to check that out too

[black2door]

Ok thanks alot for all the help guys, i guess it will just be alot of trial and error.