Vibration is still there :(

[az2md]

I just got my car back after getting the front lower arm bushings and ball bearings changed but the vibration is still there.[V]
I feel the vibration through seats and the floor of that car and it starts at around 55mph and goes up to 65mph. Its goes away if you are not in that particular speed range. Its more when I am accelerating between 55mph and 65mph. The mechanic told me that he had done a Road Force Allignment and the tires are out of round, in other words, are cupped. Can anyone tell me if they are cupped, why do I feel the vibration only when I am driving in that particular speed range and especially when I am accelerating?
Any input from you guys is appreciated.

Thanks

[rob_fed]

The W210 is very sensitive to tire/wheel changes. If you search for past posts, many have varied tire pressure, just a few pounds, to eliminate various noises or vibration felt throughout the cabin.

Because you are experiencing vibration on within certain speeds, then you are experiencing some sort of harmonic imbalance. At about 60mph (+/- a few mph), the tire/wheel is rotating at right speed to get the whole assembly to move up/dwn very quickly. If you tires are cupped or out-of-round, then this movement is amplified even more. A bent rim on the inside edge of the wheel can cause some real vibration too.

Not sure if you car is lowered stock height, but lots of W210s at stock height have a little more outside tire wear, in which this area some times gets cupped or you can see variations in the height of the outside tread. This sometimes is felt as vibration, but not necessarily a true harmanic imbalance, it is usually heard as increased road noise.

Unfortunately, at the same speed, about 60mph, you can also experience drive shaft problems. I am not familiar with the design of the W210 driveshaft and attachment points. But worn u-joints, bearings, and bent driveshaft can be felt through the seat of your pants at certain speeds.

If you feel a slight vibration at 35mph too, then you know that you have real harmonic problem. Which are hard to find, even for the so called experts.

a. Lets assume that it is your tires, I would have them rebalanced at a reputable shop. Ask the technician to inpect both sides of the rim and to evaluate the tread wear across the tire surface. Also ask the tech for a full dynamic balance (weights on both sides of the wheel). Many times, if you have aftermarket rims, even when the tire/wheel is spin balanced, the machine is in static mode to only indicate the static position of the weights to keep them on the inside.

Note: A good shop can still keep the weights on the inside of the rim and perform a dynamic balance by splitting the weights across the inside surface.

Also, if the tread wear pattern is severly cupped, then no amount of balancing will fix vibration.

b. If your tires/wheels check out and you did not need a huge amount of weights to get the wheels to turn smoothly. And you still have your original problem, you will need to move on to the driveshaft.

Many newer shops have elevated dynomometers. The tech can inpect the driveshaft while it is rotating at the offending speed. It is pretty apparent when a driveshaft is bent or something is not balanced. But the fix is not always found the first time around. There is a lot of trial and error in this area, unless, there is a typical problem with certain vehicles. But from this forum, and *.org, driveshaft problems do not seem to be common for W210s.

Hope this helps,

Rob Lee

[az2md]

Rob,
Thanks much for your detailed explanation. My car is a 97 and I bought it 8 months ago with 27k miles on it. Now it has 39k miles and it has been giving me the vibration problem ever since I have bought it. After what the mechanic has told me with the Road Focre balancing, I am thinking of changing the tires as a first shot to the problem. The car seemed to have been sitting for a long periods of time before I bought it (extremely low mileage on it being the evidence of that).
I have found a good deal on Bridgestone Potenzas and am going to get them on Saturday. There is a good deal on the Michelin Energy MXV4s as well but thats what I have on right now and am pretty turned off with them due to this vibration problem.
Will let you know how this test turn out. With new front lower arm bushings, new ball bearings and new tires this problem needs to be fixed.

Once again Rob thanks for your input.

Paul

[rob_fed]

Wow 37k on a '97. Thats great! There could be room for debate whether your radial tires are "flat spotted" due to extended storage. If they are the originals, the rubber is probably very hard now. Flat spots would amplify the 60mph harmonic problem too, but you should feel something at 35mph too. Could be just enough variation to be a nuisance! Vibration problems are hard to debug. But I think you are on the right track!

[az2md]

Once again thank you so much Rob. Well, I just pulled out the work order from the recent trip to the garage and there is a note on the top reads:
"After Road Force Balance, two rear tires show 23lbs of road force".
As far as I remember reading somewhere, the road force has to be around 10 lbs. Is that true? Also a coworker of mine who knows cars drove mine yesterday and he thinks its not the tires as the vibrations seems to be more when we are accelerating (55 to 70mph range). Any suggestions? Could the tires vibrate more when your foot is on the gas and less when you take it off of it?
BTW, if anyone is in the market of purchasing tires, Costco has a deal on Michelins, Bridgestones and BF Goodriches ($60 off four tires, expires 02/01/04)

Thanks

Paul

[mbenzman]

The Michelins have the least problems of all tires - period! Buy them from an authorized Michelin dealer who has a Hunter roadforce ballancer. I use a tire store that has this. To me one important detail is that they use the original M.B. wheel weights (two pieces, weight and clip) to prevent damage to the wheel finish. The aftermarket weights gouge the lip every time.
When they install the tires and roadforce them if then they find a issue w. the tires they can warranty them as Michelin will accept the roadforce values.
The Hunter Roadforce machine feels and measures the contact patch of the tire under load with a wheel it presses against the rotating tire with great force to simulate your contact patch. Any variance in the rotation is measured in pounds of difference (flatter, harder, softer, or out of round). At the same time this machine tests the rims for out of round and will calculate the best match and position to relocate and orient all four tires to try to shuffle and match out of round rims to out of round tires and create round assemblies.
I know shops that have invested in a Roadforce but are too lazy to use it. Its sounds like you have a decent one.
Did you really have ball bearings replaced or the front lower balljoints? I would bet balljoints.
Your vibration sounds typical of tire problems and since he has given you a value from a Roadforce you should fix what you know is already wrong. See if you are still having a problem after that.

[rob_fed]

Sorry to hear that you are still experiencing problmes with your particular vibration.

In your original post, you had the lower control arm bushing and front wheel bearings??? (ball bearings???) The only other replacable parts in the front end are the upper control arm bushing and the ball joint. With only 37k, it is hard to believe that these items are worn, except if the previous owner raced or beat the hell out of the car.

In the modern automobile, ball joint loosness is hard to detect by raising the wheel off of the ground and grasping the tire. Your may have to use a pry bar between various front end components to see or feel if you have any play.

I haven't read very posts related to major front end problems with the W210, I had a '94 540ia that was plagued with a major front end design that allowed the upper control arm or thrust arm bushings to wear out very quickly (20k - 30k miles).

Lets look at the problems another way. Do you now only experience the vibration during acceleration? Do you feel any vibration during braking?

Also, do you hear any funny noises during the vibration, like clunking or bumping sounds?

As I indicated, these things can be very tricky. I assume the suspension has not been modified, lowering springs, etc. Even so, no one has complained that these components have lead to new vibration problems either.

Try to take your car to a shop with a dynomometer. Have the car tested or at least driven up to the speeds where you feel the vibration. Since the front wheels will not be turning, if you do not have the vibration, then you know the problem is still in the front end. If you do, then it is time to look at the rear wheels/tires and/or the driveshaft.

The W210 does have a center driveshaft bearing, in other cars, when this wears out, you can feel driveline vibration. Again, this is a stab in the dark, this is not a typical area of problem in the W210.

[az2md]

Guys,
I have replaced all four OEM Michelin tires with ContiExtremes and the vibration is almost gone (99%gone). I think the rest 1% is probably just my head. I drove the car to work this morning and it is driving so much better. It was at around 45-50 mph that I felt a little vibration but then again I might just be looking for anything and everything at that point. I am overall very satisfied.
I drove in snow and freezing rain on Friday to the tire shop and the OEM Michelin tires were satisfactory on my way to the store. But when I left the store with new ContiExtremes, the car was driving so much better and I almost forgot that the road was so slick. These tires are amazing and the tread pattern not only looks aggressive but performs that way too.

Thanks to all of you guys for your valuable input.

Paul

[rob_fed]

Thats great! It is amazing how tire/wheel balance affected your car. When you have a chronic problem like yours, you are always on the defense when you the magic speed of is reached. You always think/feel the problem is there a little bit.

Also, I once had a rim that was bent on the inside lib, enough to slight deform the side wall of the tire. When the wheel was mounting on the rear, no or little vibration could be felt. Once I rotated the wheel to the front axle, then I could really feel the problem.

[hus]

my brother had the same exact problem with his BMW, the car only vibrates between 55 and 65 mph... it rides great before hitting 55 and after leaving 65pmh and his problem was the front UPPER control arm bushings. its not the tires..
hope this info helped
Good Luck
HUS.