Clunking in Rear End - PeachParts Mercedes-Benz Forum

gmaltz · #1 10-10-2007, 11:44 AM

1987 300D Turbo

I just heard this clunking noise during acceleration from a standing start. Not right away, though only at about 20 mph and then nothing. Some swaying also at cruise. Very worried, up on the lift and nothing unusual to the eye.

Then I grabbed each rear wheel. Left OK. Right is loose!

Lugs where tight so could this be a wheel bearing or an axle shaft or something else?

Car is unsafe to drive now, so any help would be greatly appreciated. I am looking on the maintenance CD now.

gmaltz · #2 10-10-2007, 04:48 PM

I found the cause!

The lower rear outer control arm bushings are worn out and loose which explains the rear end Fish Tail I have been so used to!

When I grab the rear wheel and twist, the right wheel moves a lot.

Then when I lift upwards on each of the them , they both move vertically and I can see it moving in the bushing.

The manual says you need a whole bunch of special tools to work on the rear end componants. Anyone do these type jobs whith out buying all these special tools?

ScottinSoCal · #3 10-10-2007, 06:29 PM

Quote:

Originally Posted by gmaltz

The lower rear outer control arm bushings are worn out and loose
The manual says you need a whole bunch of special tools to work on the rear end componants. Anyone do these type jobs whith out buying all these special tools?

What you're worried about in this job is the spring getting away from you. It's under a tremendous amount of pressure (1/4 of the total weight of the car) and if you let it go suddenly it can cause injury or death. What you should have is spring compressors to keep the tension on the spring and let the rear control arm go. If you're not comfortable doing this, you should have someone do it for you.

gmaltz · #4 10-10-2007, 10:02 PM

I was thinking about that too Scott.

I finally tracked down the procedure in the CD manual and guess what? Absolutely no mention of coil spring removal in order to change out the lower control arm bushing!

Go figure!

ScottinSoCal · #5 10-10-2007, 11:17 PM

Quote:

Originally Posted by gmaltz

I finally tracked down the procedure in the CD manual and guess what? Absolutely no mention of coil spring removal in order to change out the lower control arm bushing!

It doesn't surprise me. I changed the front lower control arm bushings in my car and didn't remove the wheel assembly, take out the springs or anything else. Yeah, it was potentially more dangerous than the authorized procedure, but it worked for me.

When I changed the rear subframe mounts I looked at the bushings and I wouldn't take the spring out for that, either. It looks fairly easy to get at with leaving everything in place. Fortunately mine didn't need changing.

gmaltz · #6 10-11-2007, 07:56 AM

A Klann coil spring compressor on the German tool site www.samstagsales.com costs - are you ready - $965.60 !!!!!!!

I think I will use my good 'ol American Ingenuity to do this job!

I will report back with my success or failure.

gmaltz · #7 10-11-2007, 01:04 PM

Good news.

I just purchased the removal/installation tool for the lower rear control arm bushing. It was on sale at www.************************ for only $115.95. Now I'm just waiting on the parts and the tool and maybe by the weekend I will be back on the road.