So I took the 400E out on the highway for a run after the new wire harness. Then I hit the brakes at like 65-70mph and I got a shutter throught the brake pedal, I'm guessing rotors need cutting or replacing? Off the highway I never felt that problem??

Warped rotors could cause the car to shudder when the brake is applied. A runout check with a dial indicator will confirm if the rotors are warped. Replace warped rotors. Turning MB rotors is not recommended.

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Fred Hoelzle

Did the car see any significant storage? It could be corrosion on the rotors.

It sat for awile before I bought it couple months I think!

let me clarify, warped rotors cause the brake pedal to vibrate when applied, not shutter

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1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)

Shopping for brakes I noticed that there were to different part number for rotors for my car??? Was there a mid year change in 92??? Also anyone ever use centric rotors not to familar with them?