[bayhas]

Peter Guenther - 12/1/2005 2:09 PM

That is a radical approach, higher pressures, road force balancing, is probably the answer. On my car they replaced the Pirelli tires with a v rating to michelins with an H and put a sticker on the cluster that said to limit the speed to 120. I guess the softer tires did not flat spot, I notice a certain flat spotting with my wagon and really starting to dislike Michelins.
My professioal tire guy (specializes in tires from golf carts to trucks)told me heavier car more pressure.
I dont hear any issues from the armor plated (heavy)versions , it would be intersting what they run as to pressure.
The shop forman at my local MB dealership says there was a class action suit and people got a coupon, but MB does not talk about it. I was solicitated about buying my coupon but never got it ($4,00)in 95 I think.
As the "teutonic" female says in the letters " we have attempted to satisfy your issues during the warranty period".

do you have any info, numbers, contact persons about that suit?

 

[Peter Guenther]

I only heard about the "suit", otherwise why would MB send out coupons. I did recieve at least three solicitations offering to buy my coupons for cash.
Every dealer I ever had contact knew amout the "vib" issue on the early cars, but there was no fix bulletin.

 

[NAB]

From this forum it would seem that the chassis vibration issue predominantly affects early cars. If so, does anyone know what changes were made to the front end suspension set up in the later cars which effectively made the problem go away ? I can't imagine the car got any lighter, so the tyre flat spots should have still been a problem if that was (at least one) cause on the earlier cars ?

Thanks

 

[Kiawah]

bayhas:

The vibration you experience at the 50-60 mph range (and not at 120+ mph) could possibly be some harmonic vibration being set up with your wheels. You will feel the vibration only at certian speeds - specific to your wheels only. If you could keep giong faster and faster, you might experience it again at, say 540 mph, just to pick a number.
I'm not sure of a real solution. Possibly, rotating the tire on the rim 90 degrees - just to change things around a bit. I do know that the "Road Force" balancing I mentioned earlier in this thread should tell you even which corner of the car that tire is best suited for. Below is a URL for an article on road force balancing and how it works. Good luck.
http://www.gsp9700.com/pub/technical/4693T/4693T.htm

 

[Fluteguy]

I think that once again we need to go back to the weight of the car and the height factor. After 94 the car was lowered an inch and a some of the heavier options were deleted (parking assist anntennae for one). The original list price for my 93 was $97,500. The '94's dropped almost $15,000 in price due to MB leaving out some of the heavier stuff.Again, weight and height!

 

[mbnz230]

i had the same problem, but when i replace the old tires with new one's the shakes are gone. go to a reputable tire place like tirewarehouse to balance your tires dont go to places like pepboys or walmart, from personal experience.

 

[NAB]

I've had this problem - with the car's significant weight it is inevitable that flat spots will appear on the tires if the car is parked up for any length of time. Especially the front tires. Apparently flat spotting is more likely on wider tires - and the W140's 235 width was a significant increase on previous Mercedes models. The problem is not unique to W140s - lots of other car and even motorbike forums have raised this issue.

Three practical suggestions (which have worked for me):

1) pumping up tires to 50+ psi will reduce flat spotting - most manufacturers do this between manufacture and delivery. Obviously reduce the pressure before driving;

2) a fast run - say 80mph + for several miles will heat up the the tires and encourage them to reform into a true circle;

3) some companies sell thick rubber matting which they argue minimises the flat spotting when the car is parked up. I have yet to try this but it may be worth a go. The weight of the car will more easily absorbed by the rubber than it will be by concrete. This should reduce the deformation of the cars' tires.

Happy New Year !

 

[jerzyboy]

I must be one of the lucky ones, but I just borught my 95 to the shop and had them rebalance the wheels and the shaking has stopped. I was pretty upset when it started.

 

[bayhas]

let me pose this question tho:

would a tire with a flat spot show its diffect when spin balanced?

 

[1999_S600]

jerzyboy - 1/4/2006 3:28 PM

I must be one of the lucky ones, but I just borught my 95 to the shop and had them rebalance the wheels and the shaking has stopped. I was pretty upset when it started.

yes. i did this as well, and haven't had any problems since.

 

[Destroyer]

I have to claim bullshit on the flat spot thing. I have a 91 Caddy Fleetwood that sat for 8 months till I got around to swapping a modded 87 L98 350 into and it did not have any vibration. I'm willing to bet the Fleetwood is heavier than my W140.

 

[NAB]

Bullshit or not, I think you'll find tyre flat-spotting is well recognised as a fact by most experts. I agree it depends on the car and the tyre in question - I also run a 7.5 tonne truck that doesn't get flat spots when it sits for several weeks. I think its a question of the make and model of tyre and the air pressure - most vehicles with a weight above 3.5 tonnes run tyre pressures of 60-100 psi. Commercial tyres will have much thicker tread and sidewalls. The rubber used will be a thicker, less "sticky" consistency and hence less likely to deform under pressure.

I'm not claiming to know the answers, but only reporting what works for me.

 

[NZ Benz]

It could possibly be the steering idler play. If the feedback is through the steering wheel. There may be a small amount of movment in the joints. Another thing to check would be the tie rod ends to see if the wheels are in sync properly. the tyre flat spotting or whatever sounds correct as I have low profiles on my '18s and after I had the tyres changed from some german ones that I didnt want to pay 1300 to buy for bridgestone gts my car developed this problem in the cold but when it warms up it stops.

 

[llast993]

do you have an update ? I have 95' S420 w/ 67,000 miles. Changed out the motor and transmission mounts not to mention a set of new tires. Still vibrates starting at 50 mph or so. Any thoughts or ideas on what I should tackle next ? TIA

 

[nhzruthless818]

mine has/had this issue mine is 142000miles driven but when ever i tighten the wheel bolts and add air it goes away on mine. i think it has something to do with alignment (on my other benz e320 when i changed the tire and got a alignment and balancing it stopped the vibration also it could be the rotors from what i hear).

 

[S666]

Might be nothing, but check for any family history of Parkinsons disease.

 

[nhzruthless818]

you made a funny. but serious you do feel a vibration at 50-60 i know mine just need an alignment since its old it might be time for an alignment. plus they tell you if any suspension part is damaged. not bad i have family friend that owns a shop and he even notices small curb rashes on the alignment. i need to take my s500 to him soon so he can evaluate it. also tire balancing does have a major role in it. plus i remember him telling me the car is heavy and the parts are old so you could expect that. did you check your rims for damages?

 

[llast993]

Replaced the tires from Costco. No issues w/ rims. I am going to take the car back to Costco this morning and have them to rebalance tires. Will keep you guys posted.

 

[nhzruthless818]

is your vehicle alignment recent(i can't remember properly but i think most cars need a alignment every 4 years or so)? i heard it cant be the mounts(engine or transmission) since its only at certain speeds. also does this only happen when cold or warm or always?

 

[MB_Fahrer]

I have a similar vibration in mine. Its definitely coming out of the rear end. So I have compiled a list of all the rubber parts and I will be changing every single one of them. I might take the time to have a few custom more "performance" oriented bushings made depending on what I find when I take it all apart. My mothers ('92 500sel) winter car has a similar issue. I will go read through the whole post to see what everyone has found but that's my $.02 worth