So i bought the 1991 740 turbo back in october and had very little problems. Recently my transmission was slipping a little bit before it warmed up and only in 1st and 2nd gear( automatic ). Last week my buddy drained and filled the fluid and it was driving great again. Then my brakes started grinding so i stopped driving for about 5 days. My buddy came over to change my pads and after he changed them i went to test it out and it barely made it off my driveway. We pushed it back up and checked the transmission fluid and it was black, it looked just like oil. There was a small leak that looked like it was coming from where the transmission either goes to or from the radiator. No clue at all whats wrong now and any help would be greatly appreciated! Thanks

 

Hmm...I hope your buddy is more qualified than a few buddies I had back in the day.Assuming he put transmission fluid in the transmission, it should be red...not black. What color is it on the dipstick? Your 91 has an external transmission cooler as well as the traditional radiator internal cooler...there is some leakage obviously. The tank could be leaking coolant into the transmission fluid but that's a bit premature at this point. Check the transmission fluid level and color and let us know.