I'm having some chassis vibrations on lower speeds, when driving on regular roads, and I don't really know what could cause them. Just a small road bump (1-2cm?) can set the vibration going, which will last for half a second before subsiding.

The same vibration can be produced (and felt) by slamming the door closed when setting in the car.

I know my rear shocks will need replacement soon, but I really doubt that they could cause a chassis vibration of this high frequency. Any ideas on other things I could investigate? Shock mounts or bushings?

Last time I had the car up on a lift, the mechanic told me that perhaps the front lower wishbone bushes need to be replaced. Is there a good way to verify this? I took a picture of the front lower wishbone bushes yesterday. Unfortunately I don't know if it looks good or bad.

Front:


Back:

 

Here's a new Lower Wishbone Bush:



The one you've pictured doesn't look bad although it's very difficult to make a visual assessment and you really need the load off the suspension to check for play.

Graham

 

Thanks a lot for responding, Graham. If you look at the second picture, you can perhaps see that there is a distance (2mm) between the metal and the rubber, on the left side.

At the time of the picture, I had the front of the car on jack and stands. Is this enough, so I could just wiggle it to check for play?

 

Yes - there is a gap there.

With the weight of the vehicle supported on stands under the jacking points, the load is off the suspension.

There's three wear points on the lower wishbones:



item 5 - front and rear bushes
item 6 - Stabiliser Link
item 7 - Lower Ball Joint

The assembly is beyond wiggling due to the weight but a small bottle jack beneath each of the arms in turn can be used to detect vertical movement in the bushes due to wear and a pry bar will reveal horizontal play. Rocking the road wheel will show any wear in the Lower Ball Joint.

If the bushes are worn, a press is required to remove the old ones and fit replacements. Exchange front and rear wishbones are available from several sources in the UK and, even with shipping, this may be a cost effective approach with the exorbitant labour rates in your part of the World.

Graham