Hello, I need some advice on my 2005 E46 325iT. This has been my daily driver for last almost 10years; there is about 126000 miles; and I have followed the recommended maintenance schedule with shortened oil change intervals. It has started to develop on 'odd' transmission quirk: sometimes upon a cold start it does not seem to fully engage in gear. If I rev it hard for a few seconds, it will kick fully into gear. If I was driving a manual, this would seem like I was riding the clutch. Once transmission fully engages everything runs as normal. It may be that the transmission has warmed up. As I said, the problem is intermittent and do not know under what circumstances it decides to act up. I have seen some online info stating certain GM auto transmissions have a slipping problem but it doesn't state what the 'fix' is. I have not found a local (Seattle area) transmission repair other than to completely replace it with a BMW rebuild (about $5k; not particularly palatable given the car's market value). Can you please help diagnosing and/or recommending a path to repair? Let me know if you need more info from me. Thanks and I have enjoyed reading your columns for the last 10+ years.
Thanks for your kind words on my column, but unfortunately I know nothing about automatics. Out of nearly 60 BMWs, only two have been automatics, and I've never diagnosed, trouble-shot, or installed one. I've always been afraid of them, for reasons such as exactly this. Have you looked on E46Fanatics.com?
First you need to check for any leaks on the transmission and if you find any please fix them. Second I would check fluid level and condition. Your car does not have a dipstick to check the fluid will need to get the car kinda warm and remove the fill plug on the trans while the engine is running if fluid comes out then it's full. If nothing comes out then it is low. Also check the fluid condition should not be black or have a burnt smell to it. Also make sure there is no metal flakes in the fluid either. If all that checks out then there are two paths you can go down. First is get the transmission adaptations reset and see if the issues get better or worse. If it gets worse you can do the other. Second is to do a flush with new fluid and filter set. I recommend also using a trans cleaner product called seafoam add to the old fluid drive the car hard then flush the trans. Doing a trans flush can make the issue worse so do this at your own risk.
Although I suspect you're out-of-luck and may need a re-manufactured one, I think it's worth calling up Mike's Transmission in Issaquah and seeing what Mike says. They're a few doors down from Eastside Bavarian over near Costco. I'd have him do the replacement if it can't be repaired - he's super good and honest.
Thank you all for the advice. I'm not sure what the "transmission adaptation reset" is but I'll look it up. (any help is appreciated) Recently, everything has been running normally. : /? Maybe I'll keep my fingers crossed for a while longer.
The adaptations are basically the transmission control unit making adjustments to wear of the trans and how the driver operates the vehicle. Some times this get adaption get confused and causes weird issues. By clearing them the trans will relearn to how you drive the car and the wear of the transmission components. So if there is a mechanical problem it will get worse. Hope that helps and yes hopefully it won't come back.
