In my '91 Porsche 911 (RWD), it's fairly easy to do burnouts and powerslides, especially in the wet. (I know it's childish and all, but I still think it's quite fun, so the occasional powerslide when no one is around is to be expected.)

It has a rear engine, rear gearbox, rear wheel drive, and no leaf springs. It's very cold here now (~5°C) and the tires are old and bad.

Recently, when the wheels start to let go, the rear wheels start bouncing in a way that they're not supposed to.

The car is rather old (25 years). I guess that time, abuse, etc. has worn something. But what?

Shocks, springs, bushings, engine mounts, diff or what would you think?

Not quite as bad as this, but it will give you an idea.

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  • Yes, we'd need vehicle information, but it sounds like you have "wheel hop". This is very common on vehicles with leaf springs in the rear, but can happen if the geometry isn't set correctly as well. – Pᴀᴜʟsᴛᴇʀ2 Oct 27 '16 at 12:44
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    On my SC300, it was the 24 year old rubber differential mounts that were worn and contributing to bouncing on hard acceleration. I replaced them with solid mounts and the problem is gone. The solution is likely to be different for each vehicle though. – cory Oct 27 '16 at 14:07
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    It is good to note to STOP doing the burnouts and powerslides which cause this situation until you get it figured out. If you don't, you stand the strong possibility of destroying the rear differential. – Pᴀᴜʟsᴛᴇʀ2 Oct 27 '16 at 16:05
  • I'll keep that in mind. It's hard though... very hard! – Markus Oct 28 '16 at 7:35

It would be useful to know the make and model of the car as the answer will depend on where the engine is located and how power is transmitted to the wheels but my first port of call would be to do a bounce test on the suspension to check for worn shock absorbers.

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