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View Full Version : Need a tranny expert here. 5L40E/A5S360R problem.



nonturbodan
03-24-2013, 11:39 PM
Got a 2000 528i with the steptronic 5 speed. About 135k miles. Just recently the wife mentioned that the car seems to shudder coming off of a stop. Driving the car myself I can feel what I would describe as a momentary slippage when applying power to begin accelerating. It occurs most consistently when locked in second gear in steptronic mode. You can feel the car begin to move, then it slips briefly before pulling away normally. No DSC light, no CEL. Reading out fault codes came up with a code 145 for the EGS, which is coming up as "engine torque reduction request failed". I believe thats related to a bad throttle body that has been replaced. The diagnostic equipment I was using also showed a main pressure reading at a max of 22%. Under accel it would drop as low as 3%, but with no sign of slippage. I don't know how to interpret that or if its even significant, but it seems odd.

The EGS correctly indicates which gear the trans is in at all times and no slippage occurs at any other time or under any other condition than starting off briskly from a stop. All I've done so far was throw a pressure regulator at it and service the trans fluid and filter. This didn't do anything for the problem but it does shift a little nicer. The old fluid came out amber colored and the pan was clean other than what I would consider a normal amount of crap on the magnet.

Any ideas? Bad torque converter?

RocketSurgeon
03-25-2013, 01:02 AM
Randy is a transmission expert here, he will know much more than I, but I seem to recall him saying that the computer can see a true transmission slip, and will trigger a light. So the problem likely lies elsewhere. I don't know about the torque converter, but I think that is pretty closely monitored too.