Sort of like a Jeepspeed XJ

[SByota]

Well, didn’t fix the fucking noise.... at least I have a stronger driveshaft now.

Jeep has had this noise since built, I’ve changed a ton of parts since it’s been built, but the noise continues. It is 100% coming from the front end, I can make it clunk just dropping of a curb with the back wheels flat on the ground.

Front end is all rod ends expect for the Currie Johnny joint at the axle above the pumpkin. New I joints, new wheel bearings, new ball joints etc. All the rod ends have urethane isolators to keep them from twisting and hitting the misalignments. Coil springs have rubber isolators top and bottom. Drivetrain mounted on upgraded mounts with poly bushings.


I’ve gone through it lots of times, replaced some parts (rod ends, isolators) that were marginal. Same fucking noise. A dull clunk that sounds like metal on metal. Kinda hollow and seems like it’s right under the drivers seat. I can’t find evidence of anything touching, rub marks, scrapes etc. When I built it, everything was cycled and nothing touched.

I just found the drive side axle U joint spit a circlip off. No evidence of it moving, but I pulled the axle and fixed it. Noise still there.

I would like to think I’m a pretty decent mechanic, but I’m at a loss here. Just noise from race car parts? The unibody does transmit sound really well.

Front suspension works well for what it is, 4wd works good in high and low range. No rotational noise or pop/bangs clunks when turning, crawling etc.Just a clunk when hitting bumps at speed. And the kicker, on the trail it is intermittent. I can replicate it dropping off a curb or speed bump at speed.

I beat the shit out of this thing at KOH for 3 days and it never skipped a beat, made the clunk the whole time, I just ignored it.

Any ideas before I like this fucking thing on fire.

 

[Turboyota]

Exhaust system?

Motor and trans mounts legit?

Shocks rotating in the mounts?

 

[84projectford]

Ifp bottoming our?

Check ball joints again for play?

“Frame” moving where it shouldn’t around spring or shock mount?

Bump stop catching spring or striking pad?

 

[SByota]

Exhaust system?

Motor and trans mounts legit?

Shocks rotating in the mounts?

Exhaust is hard mounted to transmission crossmember and floor pan. It had a 6” long flex coupler under the bell housing to account for drivetrain movement. I yanked and pried on all of it, no real movement or contact with anything.

I built all the drivetrain mounts. The clearance on the drivers side is pretty tight between the two sides, I’m going to pull it apart to investigate.

Shocks have the King urethane donuts in the top to prevent the twisting.

All good ideas, keep them coming!

 

[mikey09120]

Go pro under the front.

 

[Turboyota]

Go pro under the front.

Why would the GoPro make a clunking noise???

 

[partybarge_pilot]

Loose axle bearing?

 

[ucd baja]

What about the little coil spring hold down chinga-dera? Back when I had an XJ those would strip out become looses make noise up there.

 

[stockerwithalocker]

Are your uppers attached in the stock location? Hard to tell in pics. If so, check the inner section near the unibody. I had some cracks behind the upper mount that were really hard to see. Tracking that down drove me nuts.

 

[Horunner]

My old xj would clunk and id feel it in my feet/ass when the motor mount was bad. Check the mounts if they’re not already replaced with better ones.