Went to Bristol last night, and I broke something at the track. It happened during a Burnout. I felt and heard a "clunk" in the back of the car when it squatted hard. I made the pass gingerly, and felt the "clunk" at each squat when I went through the gears. I jacked her up and checked all the springs, sways, etc visually, and nothing is loose. I thought it might have been the rear end hitting a pinion snubber, but it is clean, and never touched. It is very noticably different. I made another pass to see if I couind pinpoint the location, and it is definitely in the rear of the car( so not a transmission mount) I jacked it up again, and checked the drive shaft. There is a little rotational play in the drive shaft, but I didnt see any sign of any unusual play or damage to the u-joint. I drove home from Bristol to Asheville NC, (about 90 miles) and it ran fine. It was raining, so I couldnt really test the suspensioon, but it felt OK. Maybe a little rough around potholes and bumps, but that could have been my imagination. I tested a few things as I got home, and if I punch it, even from a rolling start, I get the "clunk" But if I take off normal, nothing at all. It sounds like something hitting hard. It is a loud, very noticable metal "clunk". Anyone have any Ideas? Ill get it on the lift tomorrow, but I dont really know where to look. (I dont know about the rear end- it is possible. But i cant imagine hurtnig somethng in the rear end, then driving almost 100 miles with no problems. no whine, or anything)

 

Cut your traction control off. It is trying to keep you from spinning out. They will do that to if you gun it with TCS on. Nothing to worry about.

 

I ran without traction control all but the very first pass. The clunk didnt start untill the third pass. It isnt traction control, unless it is somehow damaged. Thanks for the idea, though. I know what you are rtalking about. It tries to prevent the burn out, and kinda feels like the car is shutting down when the traction control engages. This was not that. This is something most definitely "Broke"

 

Ah, didn't know that. It sounded like you had left it on the whole time lol.

 

Check your upper third link. MAYBE you broke it or sheared the bolt where it attaches to the top of the rear end housing. If so, put in a Steeda adjustable and Steeda torque box braces. I noticed a huge difference in launches when I changed mine.

 

I have the Steeda adjustable third link. It was fine. That was one of my first thoughts too. It looked fine, and if it were broke, leading to the clunk, there would be some evidence of somethng hitting above the axle housing, which I couldnt find. If a strut blew out, i would notice the car sitting sideways, or I would launch sideways, right?

 

How about this - When I had put in my Third link, I did not get the front bolt that go into the bushing tight enough. It loosened up a little after time and I got a clunk when I would get on it or brake hard. There is play in the mount holes and it was shifting back and forth. I put it back on the lift, rechecked my pinion angle with an inclinometer and tightened the crud out of it. Problem solved. Just a guess.[:-]

 

hmmm
that will be the first place I will look in the morning. If it isnt something like that, then It will probably be the rear end. Thanks again for the idea

 

I seriousy doubt that it is in the rear end itself. Like you said, it did not whine or act wierd on your way home. I have heard of a couple of people breaking the LCA's, but I think you would have seen that and probably have kicked sideways under acceleration. Let me know what ya find. Sure sounds a lot like the 3rd link shifting back and forth though.

 

Oh, yeah, one more thing. I did a reverse burnout, and it made no sound.
I put the line lock on, and dumped the clutch gently in reverse, and it didnt make the clunk. that would be reversing the torque on the rear end of the car, too.