Friction

I have been trying to get rid of a vibration in my steering/front end. I have reballanced (road force balancer) the wheels/tires 4 times now. I have replaced one cracked wheel, and had the other repaired for a small flat spot on it. Vibration is at highway speeds and is inconsistant varying from anoying as heck to barely noticeable (although always detectable by me). At lower speeds there is a sound kind of like a out of round tire or a wheel bearing going out.

I took the car into the dealer one more time to see if they can find the cause of the vibration. The reballanced the tires/rims one more time and found them slightly out of ballance. However when the shop manager took the car for a spin, he could detect that there is still someting wrong with the car. His dianosis is that the transmision cooler may have leaked some water into the transmision fluid somehow. He explained that since the trans cooler is at a much higher pressure, somehow it leaked into the trans fluid. That water inturn causes the torque converter to slip and vibrate. That is where he thinks the vibrating is.

They are testing the trans fluid to see if there is any water showing up in it. If they find it they will replace the tranmission radiator and flush the transmision.

I am not at all convinced of his diagnosis. I expected just to be told to buy new tires, or maybe they would find bad wheel bearings or a faulty suspension component.

Has anyone else been theough the water in the transmision fluid thing before? The dealer says they have seen it before.

shardul

iTrader: (1)

yes it has happened before. coolant leaking into transmission fluid. have you been loosing coolant lately?

psk145

this is interesting as I have experience some steering wheel vibration at high speeds, as well as some vibration in the car at lower speeds.

Yacht Master

Yes that happened to many C32s I believe but not many E55s.
Check tire run-out (out of round) and AirMatic shocks.
Right before I had a AirMatic strut go bad I had a bad vibration, new strut no vibration.
What kind of tires do you have? Tire could have a broken belt or bad lap joint.

Friction

Tire run out was supposedly check on the road force ballancer. All was in spec. It is possible that there is internal tire damage of some type. Would the ballancer not detect that though? Nothing is visible from the outside of the tire. I suspect either bad tire, wheel bearing or maybe the suspension. I mentioned those ideas to the dealer, but this transmision idea was what they came up with. I will let it play out since it is still under warranty. Tires are at about 50% or more tread, so I will replace those eventually. The Dealer seems to think this "Road Force Ballancer" eliminates the wheels and tires as the culprit. Are those ballancers that good?

Yacht Master

Road force is the best no question. too bad it can't balance on the car, that way the hub and rotor are balanced too.
If the (A) strut has lost even half an inch of dampening the sway bar will act as a bouncy spring on the side with a bad strut.
I agree let it play out (sounds like a free trans flush, not a bad thing).
Wheel bearing would be quite obvious.
New tires are the cheapest place to start when it comes time to throw parts at it.

prodigymb

ball joints and front control arms can cause a vibration.

bbearden

The previous owner of my car experienced symptoms which he believed was a bad motor mount. When he took it to the dealer, he found that a failed coupling introduced glycol into the trans and needless to say, the trans didn't respond well to glycol as a lubricant. Have a newer trans now and the newer style radiator. Best of luck with the repairs!

Blacksport350

Ditto on this.

The water in the trans issue us also not uncommon but I don't see how you could feel the vibration in the wheel?!

Friction

Except when you are under warranty!

itsmeek

I had the same water issue on my c32....expensive fix.

Friction

Dealer just called to say that there was no water in the trans fluid. That is good news. The bad news is that they are saying they have no idea what the problem is.

They did say that they will put me in an E class for the weekend if it is not fixed today. I have a road trip this weekend. The C300 is just not for me besides being too small for what I need the car for.

chiromikey

considering the symptoms, i second this diagnosis with wheel bearings coming in second.

Friction

Thanks for the input. I still think it is tire related, but the dealer seems to think that the road force balancer has eliminated that.

I guess the only thing they can do is start replacing ball joints, wheel bearings ar suspension parts to fix this???

I have Warranty until October...after that, I am rethinking the idea of keeping the car. I don't see anything out there that i would want more at this time, so that kinda bums me out.

psk145

at least your dealer is trying to find the problem

I would have gotten the "could not replicate" excuse

Friction

I was thinking they might say "that is normal for a high preformence car" but the shop manager drove the car and said to the service advisor "something is not right"

They still have not found the problem. It turns out theat they did not get another e-class loaner back in yet today. Long trip in a c300 is not what I was looking forward to. I would not mind suffering the trip on a C63, but the C300 and C350 loaners are just so dang slow and feel kinda cheap.

Friction

Can still in shop. Service advisor says they are talking to MB HQ for guidance. Anyone know why they would need MB guidance? Does that mean they found something bad and are not wanting or knowing how to proceed?

I miss the E55! I might hace to buy another motorcylce to hold me off until i get it back!

Friction

Got my car back today. Turns out the dealer replaced the radiator, and flushed the transmission and torque converter.

The drive back from the dealer was without the previous vibration. I did notice that they reballanced the wheels/tires again and increased the air pressure to 40/44 psi front/rear. The vibration seems to be gone. I still feel something in the steering wheel, but it may just be the road vibrations as it is not nearly as noticeable.

I am amazed that this repair made any difference.

Blacksport350

Wow, I wouldn't have guessed that that would have solved the problem. The vibration from the torque converter should have come through the whole car, not just the steering wheel. Odd but great that it's fixed!

Friction

Well, drive the car to work this morning and I can feel the slight vibration again. Problem not fixed. But hey, I got a new transmission radiator and a trans flush out of this. They did say they reballanced the wheels and found them slightly out of ballance even though they had just ballanced them a few weeeks ago.

So...that leaves me at wheel bearings?, airmatic?, ball joints,? defect in tire undetectable by ballancer? rotten luck?....all of the above?

chiromikey

tire defect is a possibility but i'm still betting on wheel bearings or ball joints.

Yacht Master

Well, your tranny is going "AHH that was nice".
44 psi is wack! set your tires back to the 36 psi.
The test for wheel bearings is pretty straight forward, and would manifest in failure in less than 100 miles if they were bad.
Again the test for ball joints is fairly obvious, with the car on the lift the amount of play in the suspension can be determined in minutes.
Can you tell us what speed the vibration is worst? and what mode C sport 1 sport 2?
If the vibration is worst at speeds under 68 try the C mode with the high ride hight engaged.
Do the test, same road same day. make notes then try it same road different day. let us know what your results are.
The next "test" would be have dealer switch out front tires & wheels with a used known smooth set from a car in their inventory.
When they change the tires have them check the wires and connections at the lower part of the airmatic strut for damage this is what controls the dampening. Then drive both cars.
If the car still has the vibration, pull a lemon out of your pocket and hand it to the SM and say replace every moving part in the front suspension.

Blacksport350

I would insist on ball joints as the next "experiment". I had this issue on my C32 with just over 20K miles.

Friction

Talked to dealer and told then I will drive it a few days and see If I can figure anything out. It feels like a tire issue, but two things point away form that. First, the balancers do not reflect a problem, second, the problem seems to be intermitant in intensity.

Friction

44 is the recomended pressure on the door sill for summer. Yes it does seem high though.

I will fiddle some more and keep you guys posted, besides, I need to vent here because the wife could not care less about this stuff.