BMW "No Reverse" Transmission Problem

-- End Ad Box --->Typically, the vehicle is working perfectly while driving
An automatic transmission is just that- automatic,forward but when it is put in reverse there is a
consequently most people tend to pay very littlecomplete and permanent loss of movement to back
attention to it until a major problem rears its ugly head.up.
Picture the scenario- you are driving along in the lap ofReverse is typically a major feat for any transmission
luxury, the satellite radio blaring and the heated seatsto accomplish- imagine the demands that are placed
on. You’ve become accustomed to theon a gearbox as it is asked to reverse the torque of
comfort level and great driving experience brought toyour engine so that you can back up your nearly 4000
you by BMW.pound vehicle.
You decide to stop at the local convenience store onBy far, the most common cause of the reverse
your way home to grab some ice cream for the kidsproblem in BMW’s is the failure of the
and a bottle of water for yourself. Upon returning to“D-G” clutch drum. Specifically, the snap ring that
your car, you start it up, check your rear view mirror,retains the D or reverse clutch breaks out of the
put the shifter in reverse and then the unthinkableclutch drum resulting in an inability for the clutch pack to
happens- the engine just revs as if it is in neutral andapply.
the car goes nowhere!The good news is that there is hope in regards to a
This article deals with the reasons behind anproper repair. The factory has released an updated
unexpected loss of reverse in certain BMW automaticpart that so far appears to be a permanent fix for this
transmission equipped vehicles, specifically the 3 seriesproblem.
and 5 series vehicles that use the ZF5HP19 orIn our testing and in conjunction with several hundred
“steptronic” transmission. This includes the popularsuccessful repairs at our facilities, the new part seems
323i, 323ci, 325i, 328i, 330i, 525i, 528i, 530i, X3 and X5to be metallurgically superior in several ways.
models well as some others built in the 1999 to presentWe have found that there is an improved radius area
model years.as well as slightly thicker casting. In addition to this, the
To eliminate confusion, this doesn’t apply togrove that retains the snap ring is also relocated
vehicles equipped with the GM 5L40 E transmission,further away from the edge of the drum.
just the ones with the sometimes problematicWith this issue addressed and attention to detail in
ZF5HP19. The 5L40 E has some issues of it’sseveral other areas of the ZF5HP19 unit, the
own that are beyond the scope of this article but aretransmission can be repaired to “better than new”
certainly going to be the subject of another.condition by a competent transmission rebuilder /
The failure rate for these transmissions seems to beremanufacturer. In fact, when properly repaired, the ZF
very high and is expected to become much more of agearbox becomes quite robust and can provide an
problem as time goes by.almost indefinite service life.