I'm new to the 86 body style BMW's. I need to find the speed sensor in my automatic transmission. I have a 86 528e. Please help me. Thanks. Jeff

what exactly is the car doing to make you think it needs a speed sensor in the transmission

The speedo sensor is located on the back of the differential.
If you have an EH tranny (3,2,1,s,e switch by the shift lever), then there's a speed sensor on the valve body (white plastic cylindrical if I remember correctly), you'll have to drop the pan to see it, but you may be ale to test it through the harness plug.

I'll second the request for why you're trying to locate it? Symptoms?