How much difference will part replacement make...

[andy77]

I have 155k miles on my 6.9 and it was neglected by the previous owner

If I replace all accumulators and all struts, how much of a difference in the drive will this make

Anyone do this and notice before and after results?


Thanks

[wbrian63]

Unless the struts are leaking externally, they do not need to be replaced. The only parts on them that actually wear on the struts are the ball joints in the bottom of the struts, and the upper rubber mounts, but both of these can be in really sorry condition for a LONG time before you really must replace them.

The accumulators are where all of the ride quality issues are confined. Once worn out, the car will ride like a fork lift. Once replaced - there is no way to accurately describe the difference.

There are 5 accumulators, 1 at each corner of the car, and a 5th used as a pressure reserve. The 4 corner accumulators have the biggest effect on ride quality. The front pair (and the 5th accumulator) are the same part, and the rear pair are the same part (different from the front/5th). Accumulators should be replaced in pairs.

Buy from a reputable seller, as the accumulators "go stale" sitting on the shelf. Saving a few $ by buying used parts is a waste of $. The MB Classic center in California will sell them for about 1K for all 5, if you're a MB Owners Club member. Better deals can be had from aftermarket resellers, but I can't guarantee how long the accumulators have been sitting on their shelves. MB Classic center sells enough to keep their stock current.

[koan]

If I replace all accumulators and all struts, how much of a difference in the drive will this make

Agree with "wbrian63"  do the accumulators first and make sure you get the proper 6.9 parts.

The ride improvement will be enormous.

No doubt you will find other suspension issues if the car has been neglected.

koan

[s class]

Replacing the struts will cost you close to $4000, and will not result in any real change unless the existing ones are actually mechanically damaged.  I replaced all struts in one of my 6.9's, only because some previous mechanic had cut them open in an attempt to overhaul them, resulting in them becoming ruined. 

My red 6.9 has about 130k miles on it, and original struts, plus 5 new spheres. It rides a hell of a lot better than the blue car (100k miles)  which has the 4 new struts plus 5 new spheres.  I attribute the difference to rubber bushes of the red car's suspension being a lot better than the blue car's. 

[andy77]

Thank you all very much for your input.  I know my 6.9 was neglected and for sure needs one new front strut, which I am going to have to replace.

I would not mind spending the money on replacing all of them just to say they are done and will last a while longer.  Since one is leaking now, not sure how far off the others are and this was another reason why I was going to replace.

I will be replacing the accumulators though as I do not know when the last time they were replaced.