transmission

[krackerjack]

Hello friends. I have a 1997 740i with 123,000 miles. As I do not drive it much ( stored during winter ). I get a hard down shift or sudden lurch forward as I am coming to a stop or just making a turn. After it is really warmed up there is no issues, coming off the freeway and manually shifting down to slow up the tranny shifts smoothly. I was told that I may have to the transmission module re-programmed or possibly have to buy a new one. Look forward to any help I can get, thanks everyone.

[MarcoZandrini]

How long ago were the tranny fluid and filter changed. Reprogramming the tranny control module (TCM) would work only under 2 circumstances: the program has been corrupted or BMW (really the manufacturer ZF) has come out with an updated program. I recommend that you find an independent shop that specializes in bimmers and have the TCM scanned for codes. But, I bet the tranny would benefit from fresh tranny fluid and a filter.

[krackerjack]

How long ago were the tranny fluid and filter changed. Reprogramming the tranny control module (TCM) would work only under 2 circumstances: the program has been corrupted or BMW (really the manufacturer ZF) has come out with an updated program. I recommend that you find an independent shop that specializes in bimmers and have the TCM scanned for codes. But, I bet the tranny would benefit from fresh tranny fluid and a filter.
Thanks Marco for our insight. I bought the car last year, the owner drove me around the city and out on the highway. The car ran smoothly as for the fluid being changed...not sure but I will get that done. Thanks a lot, will let you know later.

[ELVA164]

When you have the fluid changed, make sure it's a full flush and not just a "drop the pan" job. There's a lot of fluid in any auto trans that won't come out of the pan without flushing the whole system.

[beshannon]

Six months after having those symptoms (which only got worse) BMW replaced my entire transmission.

Good luck!