1992 525i Auto Trans question

Greetings all,

I appreciate everyone's help with my gasket issue, finally got that
resolved. I am the 2nd owner of the car (1992 525i, Touring Wagon) and the
owner went to the dealership for all maintainence. Since they had those
records, I asked when the auto trans service was next due (the car has
150k). The tech said that the trans was sealed for life and did not require
service.

My question is, it seems that even though the auto trans is good for the
"life" of the car (probably 100,000 miles), at some point if its not
serviced or at least the oil/filter changed, problems will happen. Does
anyone have any recommendations or thoughts on this? Thanks!

- Scott

I have two 1991 525i's with the very same transmission as your car has. It is
a GM auto tranny. They are frequently called "sealed" by idiotic mechanics
because after 1991 BMW stopped including a dipstick/fill tube on them. Both of
my cars do have the dipstick/fill tube, but sometime in late 1991 they ceased
to exist, even though the tranny is exactly the same in all other regards.

They can call them "sealed", or whatever they like, but the fluid is certainly
not lifetime! Around 1994 or 1995 BMW started using what they called
"lifetime" fluid (still a misnomer as it needed replacing at infrequent
intervals, like 80,000 miles) in some of the V-8 E34's. I don't think that it
was ever used in the E34 525's, and if it was it wasn't until the very end of
the run, around 1995. All of my repair manuals give instructions for replacing
the fluids in the auto trannys, even those that do have the so-called
"lifetime" fluid. I continue to be shocked at how many tranny techs tell
people that the fluid never needs changing, especially in the cars that don't
use the "lifetime" fluid.

Your car was originally designed for Dexron II auto tranny fluid. I am
currently using an updated version, Dexron III in both of mine. This fluid
should be changed on a regular basis. I change mine every other oil change, or
about 20,000 miles. That is probably a bit anal, but I know of some people
that do it even more often. I wouldn't go longer than every 40,000 miles under
any circumstance, though. Draining and refilling the fluid only gets about 60%
or so of the old fluid changed, but if done often enough the fluid should stay
fresh enough. I, also, drop the pan and change the tranny filter every other
fluid change, or about every 40,000 miles.

When I first got each of my cars, what I did was even more anal. Since I had
no idea what the service records were on the cars, I drained and refilled the
fluid several times over the first few months I owned the cars. After each
fluid change, I drove the cars a couple of weeks or so and then did it again.
This insured that I would end up with mostly new fluid in the tranny. The
Dexron III fluid is very inexpensive.

Even though your tranny has no dipstick/fill tube, like mine, it still has a
drain plug and fill plug. Certainly not sealed and certainly not unable to be
serviced. It is a bit more difficult, though, than with mine since it all has
to be done underneath the car.

You are an astute owner, as most people would take what they are told by tranny
techs as gospel and never change the fluid. That would mean that the tranny
would probably fail sometime after the 100,000 mile mark, as so many are
reported. Both of mine are in the 150,000 mile range with no problems, and all
of them that I know of that get regular fluid changes have at least that many
miles on them.

Dick Schneiders