87 560SEL accumulator changed rear suspension still riding rough - PeachParts Mercedes-Benz Forum

wawago · #1 05-04-2007, 02:19 PM

Hi,
I have a 1987 560SEL. The rear suspension has been riding rough (clunk gunk when over bumps) and low for years. Recently I have changed the two accumulators. The ride has improved about 50% but some of the roughness and low rear suspension still persist. I am thinking about changing diff., subframe, and upper&lower strut mounts to eliminate the roughness. My question is how can i test whether the struts (shock absorbers) need to be changed too? Last to change spring shim do I need to compress the spring? Thanks very much

Rick

dpetryk · #2 05-07-2007, 08:56 AM

You did not mention but I assume that you bled the system for excess air. If not do that first.

Then read on;

Changing the strut rubbers and subframe mounts is a good idea but it might not cure the real problem. Generally if the struts are not leaking they are good with one exception. I have found that the ball joints at the bottom of the strut can wear out. The ball joints endure a lot of force as the car bounces. I checked mine and they had some slop in them which can cause clunking and bumping. You can check them easily by removing the two bolts holding them to the trailing arm and then jack up on the trailing arm so the spring compresses a bit. The you will be able to check to see if they are stiff or not. If they are easy to move they are probably shot. Normally you are not able to swivel them by hand. They should be really stiff. Mine actually were sloppy and had a lot of play.

However that being said, I replaced the ball joints without removing the struts from the car and I still had some clunking going on. It turned out that there was a little air in the lines / struts / accumulators somewhere. I opened the bleed valve on the leveling control valve and had fluid with very small air bubbles came out. Almost like light foam. There was not much air but bleeding it cured my problem. I just continued to bleed the system until it was free of air and that did it. I used a clear plastic hose attached to the bleed valve to see when the fluid was clear of bubbles. You might have to do this a few times until all the air works its way out. Bleed, drive, bleed, drive - you know the routine.

If you get the problem solved please let us all know what the problem was.

zcc · #3 05-07-2007, 01:41 PM

If the car is over rised then it will cause rough/bounced riding.