i have a 2004 545i and the usual transmission problems for the tiptronic. I've had the mechtronic sleeve and pan/gasket/fluid already changed to fix a leak. The car will still get locked up if I push it. It will go into a fail safe mode locking me in 3rd or 4th gear until i turn of the engine.

My local BMW mechanic that i believe to be pretty knowledgable about this car believes it's the valve body seal. He's telling me he had a customer that had the same problem. They replaced the seal on the valve body and that fixed it. They would have to lower the pan to get to it.

I told him i had the mectronic sleeve replaced recently, but he said it was another part. He's asking for 700-800 to do the repairs, so I thought i'd ask the community if they thought it was worth it. If you have done the service, did it restore your transmission?

 

Tell him to hook it up to his BMW diagnostic machine to tell what the problem is FOR SURE before you drop $800 to fix something that may not be causing your issue. With that said, he is absolutely correct. The Valve Body will cause this issue as well as jerky tranny like hard downshifts and reverse issues when giving gas (jumping in and out of gear)

 

they are two different things.

the mechatronics sleeve just seals the external electrical connection to the trans.
the valve body is what diverts the fluid and controls the transmission.
attached is what the valve body looks like. it would have to be removed to reseal.

 

Thanks. The dealership that performed the previous service said the clutch e was slipping after they plugged it in.

My independent mechanic said that's the same code his other customer was throwing.