929 Rear end loose on bumps (4WS)
 

Hi all, sorry if this has been covered but I cant find anything and I need help!

I have a 1992 929 with 4WS. When driving (seems worse around 80km/h but happens at all speeds) along a road thats rough with pot holes, just large bumps in general and even man hole covers, the rear end kind of steps out like it wants to fishtail and you have to catch it. The rear swerves quite badly. It gets quite scary, especially at speed. I saw it in one other thread but there was no definite answers. I presume its not normal but I have never owned a 4WS car before either so Im unsure.

Any help will be much appreciated so I can drive without being on the edge of my seat. Cheers.

I am not sure if the rear axle steers mechanically or based on flex at bushings. If it is mechanically connected to the front steering than you need to check all linkages, I mean tie rod ends, ball joints, swaybar links, control arm bushings, anything that moves or pivots. I bet your suspension is also noisy when hitting little bumps in the road. Wear and tear on the linkages should be quite obvious. I use a tire iron wedged over a control arm and under the sway bar and I watch the links when I push up on the sway bar.
If you are unsure, watch some youtube videos on how to check and replace tie rod ends, bushings, swaybar links etc.

If the rear steering is based on flexing bushings you still do the same checks and you will most likely find that he bushings are in dire need of replacing.

I don't have a 4WS car. But I am sure it is no witchcraft.