As you probably read... my 2003 S500 had a crazy bad shimmy when I first bought it... you would bring it up to 40MPH and the passenger seat would shake like crazy.

Took it to the dealer, they said the front tires were shot. Replaced them, the shimmy is gone.

So then the car vibrates, but not violently, just like a tiny bit exactly between 65MPH and 75MPH (No joke, exactly at those speeds) but not ALL the time, but most of the time.

Took it to the dealer, they recommended replacing the rear tires. Done.

Still does it, not as much, but you can still feel it a tiny bit, same exact speeds, 65 to 75.

Any suggestions guys?

 

Oh and by the way... 0 to 65 it's as smooth as butter. Any where from 80MPH upto 125MPH, it's still smooth as butter. Only between 65 and 75 do we get the slight shaking. And it feels like it's sort of from the back, but I can't tell really.

 

Also, these are stock MB rims, non-AMG, with all new stock Continental tires.

The dealer of course did alignment and balancing when installing wheels.

 

Check you lower control arms, inspect the suspension components and go to a tire shop and balance all 4 tires again.

 

Almost any rotational member has a certain harmonic point that will result in a vibration. Unfortunately, many tire/wheel sizes seem to be the worst at our normal highway cruising speeds. I agree with Ken in that you should rebalance all four again and maybe you can change the vibration point slightly higher or lower and make it acceptable. By the way, my 01 S500 with Conti tires exhibits the exact same scenario to which you refer.

 

My thought is the Conti tires...or it could be a rim or two. Have someone reputable check each wheel assembly for lateral runout and for radial out of round. This can be done with the wheels on the car and the gage on it's stand.
Go to this link for a good explanation...http://www.yokohamatire.com/utbalancing.asp

Some tires (in my experience, especially Contis) are not built to the precision in this category that others are (i.e. Michelin/Bridgestone). Most tire manufacturers will adjust for out of round with a new tire. Remeber...you can balance a box but it won't roll worth a damn!

I had a BMW 540I that came with Contis and I went through 3 sets before I found 4 round ones.

I have the OEM Michelin MXV4's on my S500 and they are smooth from 0~130.

I also have Michelin LTX/M&S on my F-150 Super Crew 4x4 and they are smooth also, with 40K miles. I also here good things about the Bridgestone products.

In any case, keep exploring untill you get it like you know it's supposed to be...it will pay off in the end.

 

Thanks for your suggestions... it just sucks that I spent $120/tire at MB.

I should have probably bought some better ones from the get-go.

 

Take your car into Sam's Club or some other type shop and have your tires rotated and balanced. I just did this yesterday, thinking I was going to have to spring for four new tires. For $15 bucks I now have the smoothest ride in town, and can spend the $750 I would have spent on new tires on something more fun! Good luck.

 

I can only confirm what Spink49 says about Conti . I had the same thing with my Contis (245/45/18"). It took 3 or 4 times to get them rotated and what the tire guys call "matched" to get an acceptable ride. Still at ~70-80mph (little) vibs (and noise) are noticeable.
Next tire set will be Michelin or Pirelli!!!!

 

It pains me to read this because this is the exact problem I am having with 4 new Conti's. The dealership has balanced all four tires while on the vehicle replaced 2 or 3 tires because they were no completely round and done the alignment. So with all this being done I no longer have the shimmy between 60 and 70, it now occurs between 65 and 75, not before or after those speeds. Thank goodness all the work has been done on the dealers dime! I plan on upgrading to some 19's or 20's from the 17's so hopefully the problem will go away.

 

I also have this problem after getting my 19s, but the vibration seems to go away after the tires warm up. Should I get these babies rebalanced? They came balanced, but I guess flat spots were created during shipping.

 

I agree about lower control arms, and ball joints too. I had the same problem, but after I changed them the car runs great.

 

Interesting to hear this as I have the same exact issue. I am running MXVs and they are about 60% worn. Just started happening a few months ago. At 72k miles, I am on my third set of MXVs and this has never occured as the tread wore down, so although it could be be balancing, given the age of the car, I am inclined to believe it might be the lower control arms or ball joints (thanks ken!!). Will have it at the dealership in a few weeks, so we shall see..

 

Newton,

Which tires are you running? If you are running a summer Ultra High Performance tire, you will experience some cold weather flat spotting at tempeatures <50 deg F. As the tires warm up the ride and grip will improve. Houston is right on the line as to being a location where you can run "summer" tires year round. Memphis, Nashville, Birmingham and Atlanta get too cold to run those tires year round.

If you are into the high performance tires, you will notice a big difference when the temp moves to the mid 70's and 80's in about 5~6 weeks.

I know my Kumhos came with a warning on the lable that reccomended that they are not designed to be used in temperatures at or below freezing.

 

Thanks for teaching me something I did not know! It's been averaging 40s around here lately, 30s last week. This is the first time I got ultra high performance summer rubbers on this car. Last week the car was vibrating a lot on the cold highway. Didn't make sense to me as they were balanced and had weights on them. Perhaps I should try more air pressure? I'm already at 34/36 FR.

 

You can play around with it but the big difference is going to come when those tires warm up. You will really feel the grip when you get them hot and have the Airmatic on firm. Try a sweeping freeway entrance ramp at a faster than normal speed (not too fast) and it will feel as if you are on rails!!! Untill the temp gets up above 55~60 F you will have to drive at 50+ MPH for a few miles before they warm up.

 

Good advice. Warm them up.

When I drove the M3 is sub 40F temps, it always vibrated. About 10 mins into it, the annoyance would go away. I suspect "softer" tires are more prone to this.

 

I was dealing with the same excat problem, and i can assure you for the most part it is NOT THE TIRES. I have been researching this for about 6 months trying to figure this problem out, I have just recently figured the problem out. it is your front bushings.

The dealer told me the same it was my tires i have 35s on 19" so i put my stocks back on and brought it back to the dealer they could not explain it then my car was in a accident had everything replaced in the front suspention minus the bushings. still had the shake I read a good post on here awhile back about the W220 having bushing problems which caused the car to shake at 60 to 80mph. So i mentioned the bushing to the dealer and it was like a lightbulb went off in my reps head. they replaced and now my car rides like new again.

 

I did not have the vibration until I put my 19s on. So in my case, I will assume its the tires.

 

yeah if you did not notice until after you got your rims then it maybe the rims but if the tires are new it will not be a tire issue. Here is a list of "non suspention" problems that would cause your car to shake.
1. Rims and Tires need to be balanced, or was not done right the first time.
2. Rims are bent or wharped, the rim will look perfect from the outside but on the inside there will be a slight bend that will cause it. this happens often of replica rims ( i know i have some lol)
3. Tire has a gash on it or uneven wear caused by alingment
4. This is rare but the one of your tires in defected or has a bubble.

I hope this helps and if is one if these consider yourself lucky the cost of all new bushing are about 1200 from the dealer.

 

O and by the way Newton Sweet car!!

 

Wherever you go make sure they are balanced on a Hunter Dynamic Road Force machine...I'm sure the dealer has done this already, I am leaning towards the Conti's being the problem, I haven't had any luck with them either on the high-end, their CH95's do well on our lower end cars...You should try the Goodyear F1 GSD3's, coming from Conti's on the 740 they were a dramatic improvement..

 

Newton..

You know I've been reading your post for weeks and I just realized you are right down the road from me. I am in Austin..

Anyway. Your tire issue is the tire. not the car. I have 19's as well and if I let my car set for a few days outside, it feels like the tires are not balance at all when I ride on the freeway for about the first 10 miles because they get flat spots then it gets back to normal. For this reason I keep my car in the garage when I am at home cuz it's warmer and the tires don't take that long to warm to the road.It sucks when I leave it at the airport and return from a trip because I am almost home before the car smooths out. Sometimes I take the long way just to get the tires round again.

I have had these wheels and tires on two cars ant they did the same on both. I am running general exclaim which I hate because they are noisy, and the balance doesn't seem to last long.Plus they flat spot easily. I'm changing to TOYO soon as it warms up to hopefully get a better ride.

I have to balance my tires once every 4 to 6 months otherwise they get slightly bouncy at freeway speeds. I don't like driving down the highway and my passenger headrest is dancing because of the harmonics...

Also, be careful who balances them. It doesn't have to be the dealer, just make sure they are balanced 0-0. some shops don't understand that these cars don't like .25 oz differences where most domestics are not that sensitive.I can literally feel the difference when they are not 0. sometimes the shop's balancer is out if calibration just a bit and they don't know because they don't do a lot of high end cars.

I use Discount tires because of the free balance program and I do it frequently. BUT I use the shops that I know do good balance work, and keep their machines calibrated. Not all of them do.

Another point. Rims you use MUST have a center bore of precisely 66.56 otherwise you have the same problem unless you have very expensive tires put on to compensate.

Hope this helps... I'll holla when I'm down that way ballin' outta control

 

Hey there fellow Texan! Thanks for all the great info. As you can tell, I don't know a whole lot about tires, but I'm learning everyday. Thanks again!