I know these things have been discussed over and over but I'm still not sure of these. Should these thing be normal on a 1986 w126 420sel....?

1. The brakes always squeal in reverse.
2. The car slams into reverse when its warmed up, but never on the first backup of the day or if I put it in park before I reverse it's somewhat of a lesser blow.
3. In the morning, when I put the car in reverse or drive, I feel and hear creaks and grinds coming from the front and rear of the car wich go away when the car is warmed up.
4. The brakes make grinding noises when I come to a stop when the cars not warmed up. And no, the pads do not need to be replaced as they are under 50 percent worn.

Any help on this would be appreciated. Thanks

1. The brakes always squeal in reverse.
(A) No, there is something wrong = time to inspect your brakes.
Brake: http://www.peachparts.com/shopforum/showthread.php?t=142411


2. The car slams into reverse when its warmed up, but never on the first backup of the day or if I put it in park before I reverse it's somewhat of a lesser blow.
(A) Transmission: http://www.peachparts.com/shopforum/showthread.php?t=142395



3. In the morning, when I put the car in reverse or drive, I feel and hear creaks and grinds coming from the front and rear of the car which go away when the car is warmed up.
(A) Suspension: http://www.peachparts.com/shopforum/showthread.php?t=142397
Steering: http://www.peachparts.com/shopforum/showthread.php?t=142398



4. The brakes make grinding noises when I come to a stop when the cars not warmed up. And no, the pads do not need to be replaced as they are under 50 percent worn.
(A) No, there is something wrong = time to inspect your brakes.
Brake: http://www.peachparts.com/shopforum/showthread.php?t=142411






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My 1985 W126 380SE does the EXACT same thing. When the engine is cold, it glides into reverse. When hot, it slams into reverse. I asked about this here as well when I first got my 85' 380. I never got a "proper" answer though. This is something that I have lived with over the past 15 months I have owned it. It has not gotten any worse. I have discovered that if I do not apply the brakes when I shift into "R", its not as bad, but this is a 85' car. Not sure what year MB had the "safety interlock" where you had to apply the brakes before you could shift. Perhaps it was 1986? I say 86' because I think that my old 86' Honda Accord had that feature and surely MB did as well.

Those links WHUNTER posted are most informative, however, I did not see anything pertaining to this particular woe, unless I overlooked it. Knowing our luck, it is probably something $$$$ to repair. That always seems to be my luck.

Good luck.

for the tranmission, the modulating valve is the first thing you would want to measure and adjust (using a pressure guage). if it does not work, you would need to check your fluid and trans filter, while on it, I would suggest to have your valve body serviced. Those are the basic cause or symptom of a tranny going sour. You'll need a complete set of rebuilding kit consisting of gaskets and o rings. Normal for a 126 to have it service after a long miles of service.