1998 BMW E36 328i automatic transmission ( A4S 270/310R) (GM 4L30E) problems. The transmission wouldn't switch to 4th gear OverDrive on the freeway and would slip when going into 3rd gear some times. The transmission gear light would come on sometimes. The transmission had 240,000 miles on it
Here are the steps I used to diagnose the problems.
First see how the transmission reacts in Manual Mode, if all the gears seem to work well you have either a fluid issue (change the ATF) or an electronic (solenoid) mechanical issue. If it doesn't work then there is most likely a clutch or deeper mechanical issue.
In my case the transmission pan had a LARGE amount of metallic particles, indicating something inside the transmission had worn out.
4 авг 2013