BMW A4S 310R = GM 4L30E
A cure for no reverse

If your car has suddenly lost it's reverse, it could be your Tcc soleniod, when this solenoid goes out your locked out of reverse. A replacement may be purchased at, Transmissionpartsusa under its GM name 4L30E, BMW calls it module A4S 310R this may work for other transmissions too. The part is called a Torque converter lockup solenoid for 1990-1999, Part number 81396A. there is another for 2000-on. you'll see it listed when you go online. the BMW number is 24331218916. I hope this saves some of you the cost of a transmission replacement. The other reason they go out is the clip scears off in the reverse drum and cracks it.
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