Drivetrain Clunk

[spazzyfry123]

Just going to go ahead and load up the tech forum with questions I have today since I took the week off of work.

I've noticed in my 6MT car, that if I don't line up the revs perfect for the shift that I hear a clunk. It sounds like it is behind me, so maybe a tailshaft mount for the transmission? Something to do with the differential? I've heard this type of stuff before with a race oriented car with pretty solid mounts (so the transmission and diff aren't moving really much at all and the noise is actual drivetrain). But I'm concerned that this is actually a housing shifting its position from a slight shock and a bushing could be worn.

I've read of differential bushings being a quick wear item on these cars as well as motor mounts. What are typical symptoms that you will see with failing mount bushings within the drivetrain? What should I look for? I've got the week off and after a decent amount of driving in the mountains with the M3 Post crew this past weekend, I've really had an opportunity to get to know the car a bit better and recognize some things that I think may be issues or turning into one. With this time off, it might be a good time to spend some time in the garage and try to knock some stuff out instead of taking it to my shop.

Thanks!
Tyler

[R3dliner]

I would check the diff bolts and retorque them. 74 ft lbs on front and 122 ft lbs in the 1 bolt in the back. check the rubber bushings on them as well.
If that doesn't help check your guibo and u-joint. If there is play in the U-joint you will need a new driveshaft.

[spazzyfry123]

Originally Posted by R3dliner

I would check the diff bolts and retorque them. 74 ft lbs on front and 122 ft lbs in the 1 bolt in the back. check the rubber bushings on them as well.
If that doesn't help check your guibo and u-joint. If there is play in the U-joint you will need a new driveshaft.

Is it common to need to re-torque these bolts? Thank you much for providing the values!

[R3dliner]

Originally Posted by spazzyfry123

Is it common to need to re-torque these bolts? Thank you much for providing the values!

no but one of my diff bolts broke and everything was retorqued, it felt more solid.

[RomanK]

Big probability that it is left flange issue...

[1MOREMOD]

Or blinker fluid

[spazzyfry123]

Originally Posted by RomanK

Big probability that it is left flange issue...

?

[RomanK]

Originally Posted by spazzyfry123

?

http://www.m3post.com/forums/showpos...&postcount=238
From this post and the next... I have this problem with my diff.