khutchinson22

I believe it was one of the rears.

StarvingArtist

Would you like to run a test? Mark one tie rod carefully with a scribe, then adjust it one turn longer. Drive it long enough to check the vibration, then put it back were it was. If it goes away or changes dramatically then the problem is in the front end somewhere.

toledotom

Well, I hoped you paint marked the position of the driveshaft? Especially where they are tied in? Just replacing 1 section of driveshaft is sometimes a BIG No No! The drive shafts from the factories are spun balanced and marked! If you even screw up the relationship to where the u-joints tie in an slight vibration can be felt! Why do you think you have small weights stuck on the side of a driveshaft? Balance, Oh well good luck, you will notice a big difference if the support was bad. I have worked on numerous driveshafts and use a paint marker to align all connection areas with corresponding marks! If not, expect some vibration. Don't forget, these driveshafts spin at a great RPM and have torque on them also!

Welwynnick

I was wondering about this recently. Isn't everything balanced in isolation? I understand what you're saying, and I've heard it many times before, but surely Mercedes don't have a viable manufacturing process if every driveline part has to be balanced to every mating part?

That just doesn't sound like how modern automotive assembly should work. Each part should be good, and should be capable of being used on any car. I can see some possible exceptions with turbo-chargers or crankshafts, but not something as simple as a drive shaft.

I say that rather hypocritically, as I've just done exactly what you said myself.

Nick

khutchinson22

I did not mark the shaft before taking it apart. Thinking back I should have but the vibration did not change. So, either I got stupid lucky or the shafts are balanced independently. I'm thinking the latter.

I did order the rear section of the drive shaft from LKQ. Or, at least I thought I did. When the order arrived it contained both front and rear sections . The u-joint in the new one feels much better than the one currently installed on my car so I'm hoping this will yield positive results. Going to install it this week hopefully.

toledotom

I guess maybe If you want to eliminate ALL your vibration GO ahead and NOT have your Drive shaft balanced? They balance the whole assembly with u-joint on and center bearing or anything else attached! WHY do you think there are small weights attached to the drive shaft for good looks? I feel though, the vibration is coming from your suspension rather than driveshaft problems. I would look at upper strut bearing or mounts! These cars have a problem with upper strut bearing going bad and it vibrates when anytime the wheel goes UP & Down!

khutchinson22

How do you test the strut bearing?

Vr6turbo

Ive been dealing with this since Ive owned my car. I do have my original mint condition wheels I am going to swap and see the difference......but I will say I had my car on my lift yesterday and noticed over an inch of play if you hang on the rear wheels from the tops of the struts. Both sides do it like its internal up top inside the struts. Im wondering if this is an air bubble beings I replaced one side with a factory amg strut a few months ago. I do know in any of my previous VWs if that top strut bushing was loose or worn it would make weird shakes etc.... Im still thinking its my 20 inch rims and tires also noticed one side has no weights on it so Im gonna get em balanced. Also for guys with big rims, the sell these things called rim beads that go inside the tire that helps balancing issues on big rims as its pretty common to get them balanced and still vibrate. Also to mention, I worked as a STAR tech at mercedes for years and almost every one of these cars with aftermarket wheels shook. It takes a huge noticable issue with a flex disc or driveshaft to make these issues, if this saves you just parts replacing by guessing.

Welwynnick

I had the same problem. It was quite alarming how much the wheel cold move up and down, uncontrolled. Smooth surfaces were OK, but broken surfaces excited horrible vibration that was difficult to track down.

I modified my front strut top mount bushes by fitting thicker rubber bushes to take up the slack in the sandwich. It needs no special tools, costs pennies, and transforms the ride of an old car.

There's no easy way to do the same at the rear; you just have to replace the whole strut. Used units are usually fine, and again, no special tools needed.










Nick

khutchinson22

Any idea what could cause the vibration to become WORSE after changing rear diff fluid?

All the usual suspects have been replaced. Flex discs, tires, wheel imperfections repaired, trans mount, front end ball joints and control arms, drive shaft, front upper strut bushings, front wheel bearings.....there may be others but you get the idea. I'm running out of things to replace.

alskompressor

I have read through this long and painful string..you have done a lot of work! Any success since you last posted? My 77k CL55 has just started this same vibration and I was hoping to learn from your experience. Can you identify what fixes seem to help the most so far?

Shiv Sikand

Has to be the wheels

RonCL55

I agree with Shiv. It certainly sounds like wheels and tires. You are way off on the factory's wheel and tire set up for the car based on what you posted above. Even if the wheels and tires are fine themselves, you can cause bad effects by having the wrong offsets, scrub radius, etc. for the car. I noticed you previously indicated cupping on a tire and that could be an indicator of a bad set up.

Below is a site that I use to figure out wheel and tire combinations:
https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm

You can go on it and find the factory specifications for the car and then you can enter that in the wheel and tire comparison guide and enter what you are running now. You can find out, for example, what the scrub radius effect is.

I actually used this to come up with a combination that changed the handling of my car in a positive way (much tighter) even though it was off factory specs in terms of offsets and scrub radius. However, when I did that the car had significant high speed shakes until I also did a 4 wheel alignment.

So you might want to go back to the original factory wheels and tire and alignment set up and see if that solves the problem.

You will also note, that there is a guide on the link for going from 18 to 19 and 20 inch wheels. It gives the recommended rim width, sidewall, and diameter sizes as you step up. You have to vary the sidewall and tire width as you step up to keep everything working together.

gregsgroup

ItalianJoe1

Same lol. My CL has always done this, I've replaced the flex discs thinking it would help, no change. New tires, same. All suspension tight and in good working order, ride height stock, alignment perfect, all the bases covered. Cannot for the life of me figure out what causes it.

gregsgroup