my 1987 bmw325e transmission slipping on fwd, what causes the problem?
Many things can cause this issue, low transmission fluid is the first thing to check. Other issues get pretty serious fast like valve bodies or the clutch packs failing. Since the car is and older one I would check you fluid level and color and if its black and burnt replace or rebuild you transmission. Hope that helps good luck.
Hopefully you torque converter is in tact. It could contribute to this problem as well.
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