E430 Alignment Woes Continue!

MB Doc,

Well, I spoke too soon. My E430 Sport, the subject of some discussion here re: it's alignment problems AFTER the dealer worked on it, continues to show significant abnormal tire wear. Now it's wearing the inside edge of the right front tire. It appeared to be ok, but then I took an 1800 mile trip over the weekend and when I returned home sure as anything the right front is wearing badly. I personally checked the specs they set it at and it was clearly withing spec. What ion the heck can be going on here? It still pulls right or left depending upon road crown, but that's about all. Tire pressures are spot on, etc. I'm thourouyughly confused, and feeling like an idiot for ever having had them touch the thing. Tire wear was negligible at 12,000 miles, now it's significant on two tires only 3900 miles later. HELP!!!!

What is your driving style?
What brand /type of tires are on your car.
Do you have the settings that your car was at after the last alignment. Print out?

My driving style is fast but not crazy, and the wear occurred during a steady 70 mph 1800 mile round trip from NJ to Chicago & back. The tires are the Goodyear F1's fitted to the E430 Sport package. I dilligentlyt keep the tire pressures at factory spec, and I always check and adjust them when the tires are cold. (32 psi front, 33 psi rear).

FYI, for the first 12k miles it showed almost no wear, and certainly no unusual wear on the edges of the tread. As a precaurtion I asked them to check & adj the alignment as part of the 12k "A" service, as I surmized the car probably had settled a bit since new (the steering wheel spokes were ever so slightly off center compared to being perfectly aligned when new). When I got it back the wheel was significantly off to the left, and the car pulled to the right. They immediately reset it, but then over the next 2k miles it began to show accelerated wear on the outside edge of the left fron tire. They reset it again (it was toed in too much and the rear thrust was way off). It seemed to be ok, but now it's wearing the INSIDE edge of the right front tire dramatically.

I don't have the settings, but I compared their print to what MB doc gave me and it seemed to be well within spec. I'm stumped, could it be they damaged the frame and the car is now unsquare??? That's the only thing I can surmize at this point.

[Benzmac]

I think is is out of spec. The alignment can be printed at any time, so the tech could have bumped it after the printing and caused this. Have it rechecked.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

Jerry,
I do not think that you have any type of frame damage. This chassis is one of the most tempermental to align. It is very touchy to adjustments. As Iam sure that you know the caster and camber adjustments are done with offset bolt kits. This makes it almost impossible to get the alignment perfect side to side. It takes a great deal of time to get this alignment to what I term optimal. Keep in mind that most techs are paid less than two hours to perform all these operations. They are only required to bring the adjustments to with in factory spec. So please do not fault the tech. They are doing there job as best as they can.
The approch that should be taken with your car is to have the alignment done again. I do
not have the most recent specs in front of me. Your dealer will have them. I would insist that the cross camber should be no more than .2deg less being better. The factory spec is.5deg. The cross caster should be no more than .1deg. The trust angle should be 0 plus/minus .02deg
The toe should be set to the middle of the spec on each side using the win toe adjustment procedure if avalible. (Hunter Equipment) Also the wheel speaded device must be installed during the final toe adjustment for this adjustment to be accurate. On your crown drift concern. If the car is crown sensitive this is usually due to a high cross caster. But can be caused by camber as well as tires. These cars are known for following the crown of the road. Drifting away from the crown. But it should not do so suddenly or harshly.
I known that if you spend wome time around your dealer that you will find a good tech that understands the alignment procedures and I will bet that he can fix your concern.
Good Luck and happy motoring

Corky, thanks for your informative post. Here are the as-set specs on my car, direct from a printout I obtained when they checked it today at my request:

Front Camber:

L = -0.8 R = -0.9

Cross Camber = 0.1deg

Caster:

L = 4.5deg R = 4.7deg

Cross Caster = -0.2deg

Toe:

L = 0.15deg R = 0.16deg

Total Toe = 0.32deg

Rear:

Camber:

L = -1.0deg R = -1.2deg

Toe:

L = 0.31deg R = 0.26deg

Total Toe = .57deg

Thrust = 0.03deg

Everything seems within spec EXCEPT caster, which is way out. Could this be contributing to the unusual wear on the inside of the right front tire? It seems to steer ok and I've never really had wear problems from caster when it's this close side to side. Thanks again for your help!