W210 - just change 1 self levelling strut?

[pimpdriver]

My 2002 W210 (estate so probably S210) has self levelling rear suspension.

It has a random "clonk". Two different (MB specialist independents) garages have had a good hard look at it and it isn't the rear subframe bushes, and they think the only way is to change the struts. But they cost about £250 each.

The car had a pair of the spheres changed a few years ago.

Because the spheres do the damping, is it OK to just change 1 strut? (obviously I would not ever change 1 conventional shock absorber) but as I understand the way these works with the Self Levelling Suspension is different.

Thoughts please!
Cheers

Steve

 

[bob6600]

I would be inclined to change the one as it may or may not cure the fault. If it cures the fault and feels different on one side, then I would change the other.

Normally I too would change struts in pairs

 

[pimpdriver]

sounds logical.

 

[bolide]

You can change struts individually. They don't do the damping or springing. There should be plenty in breakers yards as they rarely go wrong

I am worried that they are being changed because no other fault has been found. That is not an approach I would take

With W124s I have only come across a couple of strut failures. Both involved bent struts. This can normally be diagnosed by putting the car on a ramp and lifting each wheel in turn with a transmission jack. When the jack is released, bent struts tend to extend in a series of jerks whereas good ones extend smoothly

You can get clonking from the rear of an estate if there is air in the SLS. It can take a day or two to bleed through

If the rear of the car is properly damped then I don't see how a strut can cause clonking. I'd look for loose bolts, broken strut top mount rubber bushes, ARB bushes & drop links and subframe mounts


Nick Froome

 

[Charles Morgan]

I have had a strut on a 210 estate which had leaking hydraulic fluid so was not working properly - it most certainly did not randomly clonk around, it was an easily noted double clunk over bumps.

If they aren't leaking or bent, it is highly unlikely to be the struts at fault, check as Bolide says.

 

[a111r]

Mine also has a clunk.
I read on some or other Merc forum that the bottom mounting of the SLS struts can be responsible. There again, so could the top mount.

 

[pimpdriver]

The garage checked the bottom bolts were tight and they were.

Sub frame bushes are ok.

Can you replace the top mounts easily and cheaply?

 

[pimpdriver]

Found this:

http://www.mbclub.co.uk/forums/whee...on/97323-w210-sls-rear-strut-service-kit.html

 

[bolide]

There's a spherical bush at the foot of the strut (at least on W124s) and this can seize. This causes an odd moaning noise at low speeds, particularly in dry weather. Not sure it if can cause a clunk

The top bushes aren't expensive

Nick Froome

 

[pimpdriver]

Thanks Nick.

I had a spherical bush changed, noise still there.

Will look at top mounts