I copied/pasted the rest of this from the other forum...

The first time I bought 4 tires and had them installed, I was satisfied that the car was properly aligned from the NTB in Huntsville, 3 sets of rears ago. It drove well, no pulling or lane creeping, nothing funny on the front tire wear at all. It wore the outsides of the rears (worse on the right side) in less than 4k, with cord showing. I bought 2 more and had the alignment checked again. Same thing 4k miles later.
They replaced the rears the last time for me, and suggested I visit the dealer to double check 4-wheel alignment specs. My mercedes dealer then aligned the car with less than 100 miles on the new tires, said that it was, in fact in spec, excepting a slight thrust angle adjustment, and 2 right side camber bolts. I told the technician we were looking for severe outside rear tire wear issues and he said he didn't see anything so far out that would cause that.
However, while it was on the rack, the technician (and I) saw the front of the car elevate on it's own, and return to normal height within moments. Nothing severe, just like turning the ABC off, then back on after a moment. We only saw it occur on the front suspension at that time. There were no codes set from any of the 4 corner ride sensors or from the ABC unit when it happened, it just did this on it's own. It was connected to whatever elaborate Mercedes computer at that time with nothing funny showing...
He suggested the ABC module was raising/lowering the front suspension (without setting any codes?) and that it should maybe be replaced. He told me those modules weren't 'married' to the car or VIN, and that I could try a used one if I could find one. I opted not to do that, and had cord showing on the outside edge again within 4000 miles. Worse on the right rear again, substantially.

Soooo, back to the dealership, the alignment was re-checked and was reported still within spec. My service advisor insists that the ABC must be raising/lowering the rear of the car on it's own and that's what is causing this wear. I absolutely don't believe it. The car has never appeared "on tippytoes" as it would have to be, to cause this situation. Nor has the car exhibited ill behaviour or driving posture, nothing out of the ordinary. No "occasional pulling", everything looks normal at rest, it still drives fine, all the time. The ABC and ride height buttons work perfectly, the car raises and lowers evenly and quickly in all modes. No leaking, sagging or funny sounds from the suspension. No warning lamps or codes. I pulled the rear wheels and examined everything on the rear suspension myself, to no avail. I can't see anything that looks like it's been hit/whacked/bent, there are no nicks in the a-arms or other components, no sign (to me) of anything wrong visually.


So, a couple ideas- I'd love to know if you guys agree that:

1) Something on the suspension has to be bent, worn, or mis-aligned for this to be happening.

2) The ride height adjustments (in any mode) couldn't possibly extend the suspension to the camber extremes that would cause this type of wear.

 

The SA is a goof for suggesting the ABC is causing ONLY rear, inner tire wear......or tire wear at all, for that matter.
You would feel and see your car changing ride height as you were driving or parked.

It almost sounds like your car has been lowered and the camber is out in the back......
Are you certain your car has not been lowered by any means....?

 

Vabene7

Car is absolutely stock including wheels and dealer only serviced. I am 3rd owner and knew the first 2..

There's no question that something (camber/toe?) is out in the back. The upper ABC limits or even suspension limits wouldn't allow the kind of wear I'm seeing on the outside shoulder in only 4 or 5k miles.

 

Could your ride height links be bent or broken?
These links connect from the frame to the ride height sensor......and tells the car how much to self level. I'm only guessing here.........

Other than that, I might contact a separate tire/alignment specialist and explain your issues. Then see if they can assist...
This kinda has me stumped a little, not that I am any expert.

 

Short answer is I agree with 1 and 2 above. Something is bent in the suspension, but I cannot think of what. 4k is TOO quick for almost any tire. That said, tire wear on this car is the worst of any of my others. It seems to be (a) quick and (b) uneven, and the car ALWAYS stays "within spec." The ride height thing is a red herring to me. But I'm at a complete loss as to what it can be. My indy doesn't like the way mine wear, but he never goes too far past the usual "toe in" that performance cars always spec for handling purposes.

 

I don't have unrealistic expectations of tire wear. Having put lots of rear tires on 911's and Corvettes, etc., I'm aware that 10-12K is pretty good for rears on these type cars. I just can't believe the rear suspension would be jacking itself up that high on it's own without me knowing it, or setting a code. It'd have to be at the upper suspension limits
to produce this kind of wear.

But to have cord showing on the outside after 4-5k with the inside looking new is just.. wrong. It's the wife's dd, and it doesn't see abuse. Something's gotta be out..

 

So, after getting my alignment specs from my dealer, forwarding them to Mercedes-Benz Customer Care- they stand behind the dealership's recommendation of replacing the ABC module. No surprise there. No suspension codes or faults have been set/stored, they just saw the car move up and down on it's own a couple times while on the rack. "That's all it could be" he said.

Of course, I asked "What happens when I spend $2500 for an ABC module and two more tires, and I still have the same tire wear problem?.....

"Well, then we've eliminated the ABC module.........."

 

DGulliver, This does'nt sound right, how many miles has your S55 AMG K done? Have you asked the 2 previous owner's, whom you know, if they had the same problem?

 

Sher, it's got 74k on it now. Had 55k when we got it.

Both previous owners work in my field, I know who they are, but don't know them personally. Maybe I should try to contact..

I agree it's definitely not right. I also insist it's not the ABC module...

 

Absolutely, speak to the previous owner's, kindly let us know the out-come. The mileage is still fine. They need to answer you honestly.

 

I love when these guys toss out a response like that ("Well, then we've eliminated the ABC module")...... like it's no big deal....."Hey, it's only a measly $2500."
And if that doesn't fix the problem, we can guess again and ask you to throw some more money at the possibilities. Yikes.

 

Yeah, I asked my SA in all seriousness- "What would we look at after the ABC module and new tires produces the same result- what would then be the next thing we'd do?" Because that's where I want to be..

 

My S550 was going through rear tires pretty quick, and I figured that it was from my driving style. However, my service guy @ Mercedes-Benz of Huntsville said that the mechanic noticed my car moving up & down in the rear, while it was in park! So they checked the car's computer and recommended that I replace the ABC control unit. After I did that, I haven't noticed any unusual wear, and my daily drive seems to be better. You might want to check on the price, because it only cost me about $1600, not $2500. If you still live near the Huntsville Mercedes dealer, call them and ask for Ron Cochrane. He's been taking care of my cars for almost 10 years, and he always gives me honest advice. There's also a company called LKQ, that sells used parts, if $1600 is too much.

 

thanks for all the information guys

 

If I leave my car idling for about 10 minutes, it will raise itself, once I put the car in gear, it returns to normal. I have researched this, but the info is quite limited, from what I have gathered it is a system check by the ABC.

I would look elsewhere for you tirewear, as this particular issue is doubtfully what is chewing threw your tires.

 

My 2003 S55 does the same thing....keep it idling and the car will very slowly raise itself...and then a few minutes later go back down.....my pump has been replaced 30k ago and it did it before and after...

 

Im having the same issue with tire wear but I used to think my car was dropping after idling for awhile, now I know its not my imagination.

 

I DO "EYE-BALL" ALIGNMENT and i get 10k or more out of my rear tires, that's including burn out every green light !


1st off, who ever put words in your head, CAMBER wear out tires fast,

Fact: Camber do not wear tires out that fast...

Its Your TOE alignment that's causing wear...



This might sound weird, but you have "POSITIVE" toe wear. tell your alignment guy to adjust rear toe "(-2) degree Negative" instead of (0)

that would bring your wheel straight when you accelerate under load...

IF that help, Your Thrust Bushing could wear out, (Can't see it, but you have to put a crow bar and Jerk it back n fourth...)

 

I have almost 100k on it now with rear tires being replaced every 7500 miles. Odd tire wear is on the inside tread now, and has been on every pair since posting initially. Rear (right) of car still moves up and down at idle on it's own occasionally.

I have bought a used/pulloff ABC module from an identical 04 S55 and will update again after today.

Off to have 2 more rears and module replaced. It's with the under hood electronics on the driver's side cowl, correct?

 

I got the new tires and ABC unit in, easy-peasy. Since those modules aren't married to the vin#, it was plug n' play and the car didn't know the difference.

I'll post my findings in a few days if that cured the up/down motion while idling in park. There never were any codes for any components of the system, fingers crossed..

 

Very strange problem, interested to see what happens. Hope you get it fixed. 4k for a set of tires is crazy...even the rears on a 55k AMG car.

 

Wow, this sucks...I probably would have given up and traded it in if this happened to me

 

I'm hoping it's ok now. Love the car, besides what am I gonna do, look at a newer S63 AMG? Hardly. What's mine worth with 98000 on it, $18k maybe? Lotta change to trade up, lol..

 

My 2004 S55 raises itself very very slowly whilst idling. You dont notice it until it suddenly drops itself every 15 minutes or so. Passengers think the suspension has collapsed but i know better. I think while the engine is running it must be gently building up pressure in the ABC system which pushes the car up, then when its too far high for where its supposed to be the computer must all of a sudden realise where its at and quickly drop it back down.

As you may notice my car is lowered, and as soon as i lowered it i had severe tyre wear issues on the inside of the tyres. Got it 4 wheel aligned on a Hunter Machine (which are good for aligning lowered cars) and not had that problem since. The tyres still wear unevenly on the rears, but only very slightly.

 

I wish these were worth $18k...I just looked mine up and it said 16.5K...and I'm not at 90K miles yet.

No, if I was having this type of problem on an already problematic system like these, I'd be looking at a different model. Obviously though you love the car, and it's just this one issue. So I'm not telling you to go trade it in. Shoot, I can't even keep a car for more than 2 years.