‘05 Transmission Issues after Replacement
 

I just had my transmission replaced at a shop, but when I shift into drive it automatically goes in sport then jumps to 4th gear. It occasionally flashes transmission failsafe warning as well. I’ve taken it back to them twice and they tell me they reprogrammed it, but after a day or two it goes back to doing the same thing. Any idea what the issue could be?

I would thoroughly clean and verify all of the pins in the mechetronic plug. If it is truly rebuilt correctly than my money is on a bad connection at that plug (back side of the transmission), either contamination, bent pin, plug not seated all the way and the collar locked, leaking sleeve, etc, etc causing the signal from the trans to the dme to get "confused".


EDIT: It is possible that they did not get the linkage seated correctly when they reassembled the transmission, but if you have been able to drive it for any distance, that is unlikely.. and it most likely wouldn't have anything to do with it jumping in to Sport mode - though that plug may.

Yeah I drove it for about 2 days before these issues started cropping up, so I can rule out the linkages. I’m taking it back to the shop tomorrow, I’ll make sure I tell them to check that plug. Is there any other suggestions you might have?

I am sure they know this, but also verify that they followed the BMW procedure for refilling the transmission, assuming this is a ZF tranny, they are VERY finicky about their fluid and fill process, it is super easy to fill them low.

Good point on the ZF vs. GM. So OP, you need to let us know whether you have a 3.0i (I6) or 4.xi (V8). The two transmission types are very different between the two engine types.

But in general, I think it's the shop's problem to fix at this point.

If the trans is going into 4th sounds like it is in failsafe mode. Have them do a scan to see if there are any codes, and go from there. It's their problem let them fix it.

I have a 3.0i.

It’s only actually shown trans failsafe prog once, before I took it to the shop right after the replacement. It hasn’t shown it since, but it is still doing the same thing. I’m putting it back in the shop tomorrow hopefully they can figure it out.

You have the GM trans.

Does that change anything about what I should tell the shop when I take it back in?