Diff bushing changed, clunk still there...:(

[san]

So I heard a clunk from the from the rear of my car and upon advice from the mafia members, found out it was the diff bushing that gave way...

( link to my earlier post http://www.zhpmafia.com/forums/showthread.php?14053-Mechanical-clunk-from-the-rear-end )

So I changed it the past weekend and to my dismay, the clunk is still there, albeit not as loud or as often... I am lost now and have no clue what else it can be... Checked the shock towers for damage but they seem to be fine... Checked the 2 smaller diff bushing and they seem to be fine as well...

The clunk seems to be there when I let go of the clutch gently but not always and also don't notice it when I drop the clutch a little aggressively, whereas before I changed the diff bushing, the clunk was heard whenever and however i let go of the clutch and sometimes even when i change gears...

Also before I changed the diff bushing, it was difficult to engage the car into gear and it became more difficult as the diff bushing got worse (once the car is in motion, the gear shift was as smooth as any other normal zhp) ... Now its a little easier but it is still difficult to engage in gear...

Please HELP...!

[UdubBadger]

You say bushing, yet there should be 3 diff bushings no? I replaced the front one on my m3 and its better but I still get the clunk also and I'm pretty darn sure it's from the other two.

[san]

You say bushing, yet there should be 3 diff bushings no? I replaced the front one on my m3 and its better but I still get the clunk also and I'm pretty darn sure it's from the other two.

It has 3 bushings right? One big one on the rear of the diff and 2 smaller ones on the front of the diff... I changed the big rear one...

[derbo]

There is two in the front and 1 in the back on the Non-M. You should examine the front ones as they may have been torn as well.

[san]

There is two in the front and 1 in the back on the Non-M. You should examine the front ones as they may have been torn as well.

I did check the front ones... They seem good...

[BCS_ZHP]

Also tranny bushing and engine mount bushings. With the time & age that our ZHPs are reaching, these types of rubber bushings are susceptible to Father Time.

[san]

Also tranny bushing and engine mount bushings. With the time & age that our ZHPs are reaching, these types of rubber bushings are susceptible to Father Time.

Usually after how many miles/years do the tranny bushing or geibo fail??

[san]

Also tranny bushing and engine mount bushings. With the time & age that our ZHPs are reaching, these types of rubber bushings are susceptible to Father Time.

Mine is a 2006 coupe with 96k miles

[BCS_ZHP]

Usually good for 125-150K miles or more. But Hornung (Justin) had a car where they were all going bad, he had problems shifting into gears, he replaced all at once so not sure which was the culprit. Iirc, one rubber bushing was disintegrating, likely from exposure to an earlier oil leak, oil will eat up those rubber bushings.

[LivesNearCostco]

I think Guibo can fail anywhere from 40,000 to 100,000 miles, depending how hard you drive the car. Actually my 2nd one started to fail after 20,000 miles but it was installed incorrectly and the CSB had failed at that point, which probably put more stress on the guibo.

My experience with a failed left transmission mount is it didn't make any noise and my experience with a failed left engine mount is it made a thunk when letting out clutch aggressively, because the left side of the engine would pick up and fall back down onto the failed mount with a big thunk.

[san]

I think Guibo can fail anywhere from 40,000 to 100,000 miles, depending how hard you drive the car. Actually my 2nd one started to fail after 20,000 miles but it was installed incorrectly and the CSB had failed at that point, which probably put more stress on the guibo.

My experience with a failed left transmission mount is it didn't make any noise and my experience with a failed left engine mount is it made a thunk when letting out clutch aggressively, because the left side of the engine would pick up and fall back down onto the failed mount with a big thunk.

How can I check for a failed Geibo?

[UdubBadger]

It has 3 bushings right? One big one on the rear of the diff and 2 smaller ones on the front of the diff... I changed the big rear one...

Ya that's right, was looking at the diagram backwards and since I didn't do work myself haven't seen first hand.

[derbo]

Ya that's right, was looking at the diagram backwards and since I didn't do work myself haven't seen first hand.

It's okay Seth, the M3 one is one in the front and 2 in the rear on the diff cover. :) You must've been remember your M3 one ;)

[LivesNearCostco]

Safely support car on lift or jackstands. Get under transmission and look at guibo through holes in head shielding. Might need to have friend rotate rear wheels manually with transmission in neutral to turn guibo. Seeing the whole guibo easily on a ZHP requires removing some of the aluminum head shielding.

Look for cracks in the rubber and/or exposed reinforcement threads.

How can I check for a failed Geibo?

[UdubBadger]

It's okay Seth, the M3 one is one in the front and 2 in the rear on the diff cover. :) You must've been remember your M3 one ;)

I did it on my Zhp too, coulda swore it was the same. Guess I did remember correctly just mixed up which car was which. LOL

I still need to replace those two rear ones.

[mbeckel]

Can you rule out the subframe? I know some people have had issues with it

[UdubBadger]

Could be subframe bushings yeah. But if it's an issue going into gear that would heavily suggest trans or diff right?

[Smilez]

CHECK your driveshaft center bearing as well.

[san]

Safely support car on lift or jackstands. Get under transmission and look at guibo through holes in head shielding. Might need to have friend rotate rear wheels manually with transmission in neutral to turn guibo. Seeing the whole guibo easily on a ZHP requires removing some of the aluminum head shielding.

Look for cracks in the rubber and/or exposed reinforcement threads.

Ok, Thanks! Will check probably this weekend...

[san]

Can you rule out the subframe? I know some people have had issues with it

I'm not a 100% sure its not the sub frame... But since the clunk is coming from under the car, assumed it to be related to the diff or drive shaft/tranny

[san]

Could be subframe bushings yeah. But if it's an issue going into gear that would heavily suggest trans or diff right?

Yup thats what im thinking as well...