Well there are many parts to an alignment.

Here is alink that TireRack has that will help educate you about the Alignment process: http://www.tirerack.com/tires/tiretech/align.htm

I am not sure which one it is (Toe, Camber, or Caster) but I believe on of them can be off and give you the vibration while still drive in a stright line.

Also, here is an article on Mounting and balancing. This is also worth reading: http://www.tirerack.com/tires/tiretech/mountbal.htm

MBs are notorious for becoming out of alignment easily, and wearing tires down on the sides (at least in my experience) which I why I bought a lifetime alignment plan and got the dealer to right down the specs to make sure that they are doing it right.

I would print these articles out and take them to your shop to make sure they understand what needs to be done, and have them do everything, and do it right.

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Chirag (Charlie) Patel

- 99 Mercedes-Benx ML 430 V8 w/custom TV, Video, UHF, speaker system
- 93 190E 2.6 (4-sale) w/ an amp, equalizer, and CD-changer, integrated w. stock stereo for integrated cellular phone speaker system
- had a 93 190E m103 3.2, 5-speed trans,
- had a 88 300E 2.6
- had a 84 300TD w/275k+ miles
- 2001 C-Class - Maybe (if 190E sells)