Stage4

I think my car is falling apart... first the a/c, now this. It seems the back end of my car is sliding from side to side while i'm driving. At highway speeds if I hit the gas, the rear ends slides to the drivers side, and when i let off it goes to the right. It feels like it's moving over an inch each direction. I also notice it when I downshift or upshift. It was noticeble a few weeks ago, but today it's way worse. I'm afraid my axles are going to come out. I lifted up the rear tires and tried to move the axle or rear end, but can't get it to budge in any direction. Any ideas what may be causing this? All my suspension connections appeared tight also.

157dB

Check the panhard bar for proper operation.

Stage4

is it adjustable? I looked at it and I didn't see anything loose or adjustable. I took it out again this afternoon and turned the drivers side mirror down to where I could see the edge of the rim (one advantage of having older wheels!) and when i hit the gas, I can definitely watch it move farther out from the fender. I'm at the point that I'm afraid to drive it in fear of an axleshaft sliding out! At 80mph it's dowright scary the amount of movement there is

157dB

Nope, the factory bar is non adjustable.
Its hard to see the ends of the panhard bar to check
the stock rubber bushings. One end is covered with
a piece of plastic and the other end is hidden inbetween
two sheets of the body.
Rear Suspension

Stage4

do you think the rubber bushings are shot? it's only got 12k miles on it, that seems extreme

157dB

Not for hotdogging it around with larger than OEM tires.
It is really hard on the bushings when the rear gets lowered
and the panhard bolts are not tightened up at ride height
but instead at full extended suspension travel. Or lowered
rear without loosening the panhard bolts and tightening them
back up at the new ride height with the lowering springs installed.
Thats the only thing holding the rear end from moving sideways.
I replaced my rubber panhard bushings at 1K miles with Prothane Poly
bushings and they looked all old and cracked already.

Stage4

Updated: installed new BMR adjustable panhard bar yesterday- did not make one bit of difference. What now????

And to top it off, something gave out on my turbo during the test drive.... car stalls immediately when it gets any positive boost. *sigh*

Rubrignitz

Lower control arms, upper control arm and panhard are the only things connecting your rear axle to the car. It's one of those 4 points. Have them all checked out.

Nevermind.. it's definitely the 510whp. lower the hp and your problem will disappear. j/k ;-).

Stage4

Thanks. stupid power. haha no I checked all that except upper control arm and I can't see how that would cause this. Could it be something in the axle itself? like axleshafts sliding or is that impossible?

Rubrignitz

No I don't think your axleshafts would be the issue. It has to be suspension/rims/tires related. Strange issue.

All your bushings are fine? A split bushing could cause that much movement.

I'd check your upper ca too.