I have posted about this in past, and have had this problem for well over a year now, and I would like to fix it. I have been dealing with it, but it is annoying. When I'm driving, and gears shift, or sometimes when I go over bumps, you can hear a sloppiness under car, and when downshifts, sounds like someone hitting bototm of car with a sledge hammer. I decided to change tranny mount, put poly tranny mount in, and fixed for a few days, and then came back. Changed tranny mount AGAIN, fixed for a day or two, and came back. I got under car, put up on jack stands, had wife drive, looks like rearend is moving. I DO have a spohn torque arm, and I was wondering if I accidentally set my rear pinion angle to +3, rather than -3 where I think it is, would that cause this? What exactly would cause this really annoying clunk. I have a beautiful car, but when I take someone for a ride, I have to explain this clunk which sounds like the jolly green giant just punched the bottom of my car. No visible dents or damage from under car. Please help thanks.

 

I suspect it's your exhaust pipe that is hitting on the frame somewhere. When the engine torques to the right the exhaust system moves with it and sometimes it hits the bottom of the car. The most common places to check are by the y-pipe on the drivers side and where the pipe goes over the axle. Put the car on a lift and wiggle and bang on the exhaust system and if that is the problem you should be able to hear it.

 

could be exhaust banging, or one of the cross-braces is loose.

 

Check the torque arm to see if it is hitting the tunnel maybe.

 

I have the same annoying problem. The problem is somewhere with the crossbrace/tranny mount I am pretty sure. It is only on right hand up hill turns it seems like.

I was driving late one night in the rain and long story short, I had to run over the top of a concrete landscaping block...heard a loud thump and saw the concrete block spinning in the rearview mirror. ever since I have had this just need to fix it.

 

Al, COULD be my driveshaft safety loop. Definitely IS coming from crossbrace area, and you can see the rearend torque up and down when car is on jackstands and I'm driving/shifting gears (A4) which is why I was wondering if this could be due to my pinion angle being +3 rather than -3 where it should be. Figure with the positive arc, could leave slop, whereas negative would close the slop. Any other opinoins are welcome. I'll check the cross brace tomorrow.

 

check the front mount of the TQ arm. Sphon's with the poly mount have a tendancy to loosen up the bolt holding it in. i'm assuming you have the brace mounted TQ arm. If you do I'd put $100 says it's that bolt. Check it out, then the best thing to do is to pull the nut off and put some lock tite on it, or use a castle nut and drill a hole throught the bolt. That's where I'd put my money on!!

Chris

 

yeah chris, I don't have NEARLY the power my car has, but I got under there and wiggled up and down, and it does move a little but I already greased it, and got in there with wrenches, and tightened the crap out of that bolt. It still wiggles.

 

you should only set your pinion angle to 0, more than 2 is bad!!!
the instruction tells you no more than 3 degree.

 

why is more than 2 bad? I get pretty good traction, and haven't had any problems in the past, other than this clunk. This clunk started after I first had my transmission rebuilt.