Expert: Josh Fields - 9/3/2005

Question
hi can u help
seems to be a tinny rattle from the rear drivers side when going over bump inthe road
shocks in good nick & exhaust is fine  please help  

Answer
Gary,

 I'm guessing that you have an E30 3-series BMW (1984-1991)?  If so, this is a common problem, and an easy fix.  Although I cannot hear the problem for my self, I'm pretty sure I know what the problem is.  These cars, and all later BMW 3-series cars use the same rear shock mounts.  These mounts hold the top of the rear shock in place, and allow it to dampen the vibration.  The center of the mount is a metal sleeve surrounded by rubber.  The rubber cracks, and allows the shock to pop up and down instead of compressing it.  If you want to test it, open the trunk and pull back the grey (in most cars) side carpeting to reveal the top of the rear shock.  It will be close to the back seat, so you will have to pull the carpet out a good deal.  Once you can see the shock mount, and the shock passing through it, bounce the car like you were going over a bump.  If its in good shape you should see NO movement.  If the mount is busted, or cracked you will see the top of the shock come up as the car goes down.  Sounds hard, but actually would take 10 minutes to check and replace.  The mounts can be found all over the internet and your local BMW parts supplier for $30-$50 for a pair.  And yes I would replace them both if you find one is busted.  Also if you have a cabrio, the shock mounts will be located under the top, and not found in the trunk.  
 If this doesn't help, let me know and we will try something else.

 Thanks Gary, I hope this helps....
  Josh Fields