As for the cruise control disengaging, make sure your tire pressure is up, tread ware is about the same on all the tires and the balance is correct. Having a tire or a set that is different then the others will make the computer think that one or some of the tires are turning faster/slower then the others and disengage the cruise. Just follows my theory, check the simple things first before replacing parts!
1986 190E 186K (For Sale)
(Maroon, Tan leather)
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(Brilliant Silver, Black Leather)
2002 CLK430 Sport 45K
(Brilliant Silver, Gray Leather , Birdseye Maple)