StevethePilot

Okay, I hope someone out there knows the ultimate answer and I hope it's not what I think it is. I have a shimmy in my car, which happens at about 70mph on any road, and is most noticable when I'm not holding on to the steering wheel. It's bad enough that the passenger seat vibrates as well, visibly. I took it to Phoenix Motor Company and drove a C230 all day with a black interior in the heat on a very humd day (which has nothing to do with the problem but is cathartic for me to complain about) while they put it on some sort of dynamic balancing machine and supposedly balanced the wheels, which I had to pay for because (fanfare) my wheels are chrome and therefore not "factory" (though they are factory, just with chrome on them and let's not go down that road again).

So what (other than unbalanced tires) would cause this shimmy on a truck with just over 8000 miles on it and fool one of Mercedes' very expensive machines?

oknish

JFG.

Humor me and describe your shimmy in detail. I have been noticing some vibrations in the wheel also and through the floor but I wouldn't call those as Shimmy just yet.

boxboss

So, StP, I assume that whatever your dealer did didn't help? So many things can cause vibrations.

Out of balance.
Out of alignment.
Tire runout.
Wheel runout.
Suspension parts.
Defective tire.
Did you squirt goop in a tire?
Brake rotor issue.
Over-torqued lug nut.

I have a "come-and-go" vibration. Some days it's as smooth as silk, some days a lot of vibration. IMO, it is a bad tire. When I get time (), I'll investigate more.

jpeardm

Steve, did they road force balance the tires with the Hunter GSP9700 machine? This is the only machine that can find difficult shimmy problems. The link below locates shops with the machine. It is possible the chrome process altered the stock wheel slightly. The same shop can check hub bearings and other suspension components but it is more than likely the tires/wheels.
Or just drive 55.


http://www.gsp9700.com/pub/search/findgsp9700.cfm

boxboss

The Hunter GSP9700 can detect wheel/tire runout. If your dealer doesn't use this machine, find an indy shop that does. There is none better.

You are running OEM wheels that have only been chromed? Are they your OEM's? Are you using your stock tires - remounted on the chrome wheels? Did you notice the vibrations prior to putting on the chromed wheels?

oknish

Hey, boss, good to see you back. So this vibration you talking about is it pretty harsh or is it just something that you can feel in the steering. I am trying to figure out what is it that I feel but it sure sounds like what you described. Some days, it's silky smooth and on others I can feel this vibrations a lot.

StevethePilot

Yes, PMC has this machine. Yes, they put it on this machine. I did not notice the vibration before the chroming because I only test drove it before the chroming, but yes they are factory wheels which have been chromed (I do not know what process was used but let's assume it's whatever is cheapest) so they swapped out my factory tires on factory rims to factory tires on factory rims that had been chromed and put them back on the factory axles with factory lug nuts attached the factory car.

Describe the vibration ... okay. At around 70MPH, if I'm on a straight part of the road or a part of the road where the car will follow the lane and I let go of the wheel, it vibrates about 8 degrees left and right at a rate of about 40 cycles per second, and the passenger seat vibrates about half an inch back and forth (at the headrest) about the same frequency. It's enough to make the sun visors, which move down slowly about an inch from the windshield anyway when you push them up there, to come down to a nearly vertical position in about a minute. When I'm holding the wheel against road crown or other situations requiring wheel pressure, I feel the vibration slightly but not very strongly.

When the wife gets back from Lompoc, I'm taking it back in on Monday, where they will again hook it up to the GSP9700 but not bloody well charge me again. In point of fact, if they find some other problem causing the vibration I'm asking for the fee for tire balancing back, as it clearly was not the problem.

Thank you guys for your help thus far. It's good to know they're at least equipped with the proper technology. Let's hope they get their thumb out and fix the problem, eh?

boxboss

Nish, I've been around - maybe you've missed my (few) posts.

I wouldn't use "harsh" to describe the vibration. At it's worst, it might edge on "harsh" but that would be very rare. Not as bad as what StP posted. I feel it in the steering so it's in the front wheels/tires. When it happens, it occurs around 42mph and then again around 62mph. More or less like StP posted but less in frequency and intensity. If I hold the speed constant, the vibration remains regardless of curves or steering pressure. When it doesn't happen, I can sit right on 62 without a quiver - and smooth at all other speeds as well. It happens less when it is hot.

This didn't happen with my OEM wheels/tires - only after putting on the Brabus/Pirellis. I really think it is a bad tire - perhaps a flat spot on the tire. When the tires heat up, the rubber softens a bit and is more pliable and it's less noticeable? When I get some time, I'll check into this and let you know.

oknish

Thanks for the details, boss. I need to see which speed mine vibrates the most but it's definitely at high speeds and intermittent. Next time, I will let go of the wheel and see what it does. Of course, I still have OEM wheels and tires so I am not sure how much those are to blame.

boxboss

I only drove mine on the OEM setup for 5 days before changing to the Brabus/Pirelli's, but from 0-90, it never had the least bit of vibration. So, I am ruling out any type of suspension/alignment issues - it has to be in the tires or wheels (God forbid for what they cost.) I think the first order of business (for me) is to have my tire shop put a runout meter on the tire and/or wheel and see if I have a problem there. I'm betting on a bad tire. It's possible that one or more of the lug bolts is overtightened in relation to the others and causing a touch of warp on the wheel, but I think that's a long shot with Brabus wheels - maybe with Acme brand wheels, but not Brabus*.










*I hope.

Danno4x4

Steve,

I have had a slight (noticeable only by me and not my wife) shimmy since we took delivery of our GL as well...

Just turned 3K miles on the clock and the shimmy is still the same as it was on day one. I suspect that its the tires out of balance. I plan to take it to Schumacher for the 3K hows your father with the Service Department and have them rebalance the tires in the process...

I will let you know the outcome.

StevethePilot

Danno,

Thanks for keeping us up to date. If you chromed the rims, they're no longer "factory" and you'll have to pay for the balance.

Once the wife's back from Californ-ai-ay I'm taking it back to PMC and, once they discover the source of the problem, asking for my $100 refund for the unrequired balance.

StevethePilot

So today I brought the GL back to the dealer and told them the shimmy weren't gone. They put it on the Force ... Testing ... you know, that machine you guys keep talking about. They're able to make it shimmy but NOT able to make it go away! There's a C230 (black on black) spending the night in my garage.

Also I mentioned some drift to the right, which might be just road crowning but since they will pay for one alignment before 12,000-some miles and it's at about 9400 now I said go ahead and do it. Also, I specifically asked about the long-gasp pause when you mash your foot down, and I'll make sure I have an MB Tech answer on that before I get the car back (including if there's a "fix," which it sounds like there might be on another 320 acceleration thread involving turbo boost thresholds).

So, that keeps us up to date thus far. Tune in next time, when we hear the tech say, "Yeah, sure, all Mercedes GL diesels do that! There's an option to fix it but they only sell it in Holland."

StevethePilot

STILL NOT FIXED!


I waited until today, paid for Service A because I have nearly 10k on the beast, they told me the were able to get it to wobble and "fixed" it with alignment and balancing of all four tires (uh, which I already had done once and paid for) and no sooner did I get it on the Parkway did it start shaking again. I took one of the service guys with me (who? I dunno) and had it shake for him, which it didnt' do as violently but to be nice he was large enough to dampen some of it. "Oh, maybe it's a bad tire. The force thingy [he knew the name] can't detect less than 14lbs of pressure yadda yadda." Sounds like a load of crap to me and I am getting damned tired of paying for a $65,000 vehicle and driving a $33,000 vehicle. Gettin' old. How about they take it out on the highway and drive it, since the road, the steering wheel and the SEAT can all feel it??!?!?!!! ARGH!

Thank you, I've vented now.

SToP

boxboss

Right!

Any modern day balancing machine can detect an imbalance corrected by the addition of 1/4 to 1/2 oz weight. I read somewhere that the state-of-the-art Hunter machine can detect defects (tire and otherwise) that result in 1/2lb forces at road speed.

oknish

Well, yeah, but not in case of an MB. Don't you know that they are different?

boxboss

(8o() D'oh

jpeardm

[QUOTE=StevethePilot;2349888]STILL NOT FIXED!


Steve, maybe you're gonna have take it to another shop that has the Hunter machine and get another opinion?
http://www.gsp9700.com/pub/search/findgsp9700.cfm

StevethePilot

Thank you again for the list. I agree that this is the last chance they have to fix the problem, but these guys have the GSP 9700 with the StraightTrack Lateral Force Measurement. They apparantly just don't know how to use it!

I have to keep it with MB because it's being paid for under warranty, but I think it's going to Schumacher if I don't have it fixed today.

Too much to do to have to deal with this crap all the time! It's 40 minutes (with no traffic, which never happens) one way to them. Then pay for it, wait for it, drive it 10 minutes, turn around, drive it back, drop it off again, it's just a waste of my time!

Waiting-4-550

Maybe you should get a Toyota or Lexus next time and forego the tri-star emblem

oknish

That about sums why I haven't gone to dealer with my vibration problem. <Insert a long sigh here>

eesnard

Steve,

I've got the shimmy at 55-60mph and a constant pull to the right. I installed 22" Brabus Monoblock E's with 305/40/22. Discount Tire told me I should have the car realigned when installing larger wheels. I am taking it to the dealer to have the alignment checked and then back to Discount Tire to have rebalanced, unfortunately their GSP9700 doesn't have Straightrak. Is it really that hard to balance wheels right the first time? What a pain the rear.

StevethePilot

One would expect that it would be no harder with the machine which puts actual road force on the wheel than with the simple spinning mechanism that Discount Tire has. What concerns me the most is that these were OEM rims and tires (albeit chromed rims). When I had my Lexus SC400 with chrome rims, balancing was no more difficult than with non-chrome rims. And the really big tires on my LX470 stayed balanced even after off-roading it! You'd expect a better level of service from a more expensive and exclusive car like a Mercedes than a Toyota product, and I must say that if Lexus offered a diesel in the US I'd be hard pressed to justify the annoyance of taking care of simple matters that really shouldn't be causing these problems, but I do love the look and the feel of this car - I'd just like it to be in the condition I expected it to be in, when I paid for it!

At least most everyone here's kept to the spirit of the forums and offered some extremely helpful advice. Hey, who am I to complain? The problems with my GL have put me in touch with new net-friends, some of whom I'm going to get to meet IRL!

oknish

+1

jpeardm