02 TJ Grinding / Clunking Noise

[ndisario95]

Hey all,

2002 TJ

I just had a new clutch kit and tranny mount put in over the weekend and it's great! Clutch feels great, shifts great, but now I'm having an issue where there's a grinding/clunking/groaning sound coming from underneath. You can feel it in the pedals, floor, etc. That sound was always there before the new parts but it wasn't nearly this bad and usually only happened after hitting bumps I could feel a bouncing of some sort underneath. Now it's constant. It now happens when turning it over, shutting it down, accelerating, holding speed, idling, etc. 4hi and 4lo work great, locks right in and powers ahead no problem. I just have no idea what it is. From the cabin it feels like it's coming from either directly under my feet or directly under my seat in the center. I don't think it is engine related but I could definitely be wrong. Anyone have any thoughts?

Clip of the sound:

 

[Gilaguy23]

Its pretty hard to diagnose problems without seeing and hearing in person. First off did the shop that did the recent work test drive it after the install and advise or comment. Is your rig heavily lifted as in you need a SYE due to that big lift and your DS has shot U joints, out of phase or uneven angles at the joints? The new T case mount made it worst because it raised the T case back up. Could be T case output related, or something rubbing/knocking against the body even. Just a few thoughts to toss around. Put it up on jack stands and rotate the rear wheels by hand and see and feel for the obvious noises you describe.

 

[CharlesHS]

Hey all,

2002 TJ

I just had a new clutch kit and tranny mount put in over the weekend and it's great! Clutch feels great, shifts great, but now I'm having an issue where there's a grinding/clunking/groaning sound coming from underneath. You can feel it in the pedals, floor, etc. That sound was always there before the new parts but it wasn't nearly this bad and usually only happened after hitting bumps I could feel a bouncing of some sort underneath. Now it's constant. It now happens when turning it over, shutting it down, accelerating, holding speed, idling, etc. 4hi and 4lo work great, locks right in and powers ahead no problem. I just have no idea what it is. From the cabin it feels like it's coming from either directly under my feet or directly under my seat in the center. I don't think it is engine related but I could definitely be wrong. Anyone have any thoughts?

Clip of the sound:

Do you get vibrations while driving ?
I would go underneath the Jeep and check the condition of the U joints in both drive shafts....
IF there excessive play or there is red dust between the U joint cup and the trunion the U joints are dry(no grease) and need to be replaced.
Take a close look at the front double cardan joint centering ball; look for rust or excessive movement.

Please update your Forum Profile so that forum members can better assist you with troubleshooting problems.

 

[RMETeeJay]

The tubs on these vehicles amplify everything like a drum. Great advice already from @Gilaguy23 and @CharlesHS

To me it sounds a bit like a loose exhaust, because when you tap the accelerator the noise changes. Get under there when it's cool and try to move each section of the exhaust.

 

[ndisario95]

Turned out to be the exhaust. Rear bracket weld broke and the exhaust body was bouncing around on the skid plate. Welded the new bracket in today and sound/vibration is gone. Thanks everyone for the responses! Rust is a bitch lmao

 

[ndisario95]

Its pretty hard to diagnose problems without seeing and hearing in person. First off did the shop that did the recent work test drive it after the install and advise or comment. Is your rig heavily lifted as in you need a SYE due to that big lift and your DS has shot U joints, out of phase or uneven angles at the joints? The new T case mount made it worst because it raised the T case back up. Could be T case output related, or something rubbing/knocking against the body even. Just a few thoughts to toss around. Put it up on jack stands and rotate the rear wheels by hand and see and feel for the obvious noises you describe.

Its pretty hard to diagnose problems without seeing and hearing in person. First off did the shop that did the recent work test drive it after the install and advise or comment. Is your rig heavily lifted as in you need a SYE due to that big lift and your DS has shot U joints, out of phase or uneven angles at the joints? The new T case mount made it worst because it raised the T case back up. Could be T case output related, or something rubbing/knocking against the body even. Just a few thoughts to toss around. Put it up on jack stands and rotate the rear wheels by hand and see and feel for the obvious noises you describe.

It turned out to be the exhaust rear mounting brackets. I responded to the original post with more detail. Thank you very much for the suggestions!

 

[ndisario95]

Do you get vibrations while driving ?
I would go underneath the Jeep and check the condition of the U joints in both drive shafts....
IF there excessive play or there is red dust between the U joint cup and the trunion the U joints are dry(no grease) and need to be replaced.
Take a close look at the front double cardan joint centering ball; look for rust or excessive movement.

Please update your Forum Profile so that forum members can better assist you with troubleshooting problems.

U-joints looked great! Much better than I expected. I pumped new grease in just to be safe. It turned out to be the exhaust rear mounting bracket. I responded to the original post with more detail. I have updated my profile too, I am new to the site and didn't think to look at my profile before making a post. If you do happen to take another look, let me know if you think there is any info I should add to better assist. Thank you very much for the suggestions and respose!

 

[ndisario95]

The tubs on these vehicles amplify everything like a drum. Great advice already from @Gilaguy23 and @CharlesHS

To me it sounds a bit like a loose exhaust, because when you tap the accelerator the noise changes. Get under there when it's cool and try to move each section of the exhaust.

This is exactly what it was! I responded to the original post with more detail. I gotta admit I was pretty skeptical about that being an issue but you shoulda seen my face when the whole thing started bouncing around lmao Thank you very much for the suggestion!

 

[Gilaguy23]

Good deal!! Wish every problem was that simple and cheap to correct.

 

[CharlesHS]

U-joints looked great! Much better than I expected. I pumped new grease in just to be safe. It turned out to be the exhaust rear mounting bracket. I responded to the original post with more detail. I have updated my profile too, I am new to the site and didn't think to look at my profile before making a post. If you do happen to take another look, let me know if you think there is any info I should add to better assist. Thank you very much for the suggestions and respose!

Thank your for updating what you did to resolve the problem and for the Profile information.