Automatic transmission service confusion

I want to check and service the automatic transmission in a 1994 525it. According to Bentley it is A4S 310R. Bentley suggests that an authorized BMW dealer with the appropriate temperature measuring equipment is the only one capable of checking the ATF level.
I have to assume that one of you know a way around that requirement.
Is the ATF fluid strainer the "filter"? Do you simply clean it and replace it?
I have read some interesting DIY transmission fluid changes for the e34 but they are vague in some aspects...like change the filter. Bentley does not mention a filter that I can find.
RealOEM. does not show a filter.
The transmission is fine but I want to do some preventative maintenance.
Does anyone have a procedure?
Some sites suggest that one should just change the ATF if there is any doubt about service history.

Check here. It will take you through the whole process. The transmission shown is in an E36, but it is the same transmission as yours.

I bought a laser temperature gun at Autozone for about $29 or so. I shoot the transmission pan to get an idea of the fluid temperature.

Hope this helps.

Thanks, I did actually find the site you sent me while continuing my own search. My confusion was with the word "strainer" used in Bentley. I picture a substantial, reusable, metal mesh, when I read the word as opposed to "filter" which I associate with a replaceable paper cartridge.
I must be over thinking it!
I plan on buying the filter and gasket kit and doing a atf change.
Bavauto says that a Black label on the pan indicates that Dexron III was used as original. A Green label indicates 7045-E was used and that BMW recommends 7045-E.
I have read suggestions that you should drain the atf after a short amount of driving and then refill because you cannot get all of the fluid out even when the pans are off. The second change mixes with what fluid was left and makes for a more complete change.

Originally Posted by Larrick

Thanks, I did actually find the site you sent me while continuing my own search. My confusion was with the word "strainer" used in Bentley. I picture a substantial, reusable, metal mesh, when I read the word as opposed to "filter" which I associate with a replaceable paper cartridge.
I must be over thinking it!
I plan on buying the filter and gasket kit and doing a atf change.
Bavauto says that a Black label on the pan indicates that Dexron III was used as original. A Green label indicates 7045-E was used and that BMW recommends 7045-E.
I have read suggestions that you should drain the atf after a short amount of driving and then refill because you cannot get all of the fluid out even when the pans are off. The second change mixes with what fluid was left and makes for a more complete change.

Your idea for a change after a short amount of time driving may not be a bad idea if you don't have the tranny service record, but once you do that, servicing the tranny every 30k should be sufficient. I do mine every 25k just for a little piece of mind.

i just purchased a 95 540i, with 109k I have no idea if it's ever been serviced, shouldI have it serviced, or leave it alone it is shifting sligtly rough

I recommend having the fluid drained and a new filter installed. It is generally not recommended to flush it.

+1 on above

Why not flush it? You might as well change all of the fluid right?

I have read the internet legend that a flush will somehow damage your transmission. My experience is with a Snap On transmission flushing machine, I have used it, and seen it used on hundreds of vehicles. I am not aware of a single one ever having a failure after a flush. Fluid flows through the trans as it would if it was running, no excessive pressures, no backwards flush. It is designed so that it can not possibly harm the transmission.

I think the root of this legend is so many people buying old vehicles with worn out automatic transmissions. They buy a car with a trans on its last legs, try a flush as a fix to a mechanical problem, the trans fails and they want to blame the flush. Fact is, the trans was cooked before the flush.

I have read the stories that claim sludge is knocked loose too gumming up the works. This is extremely unlikely as most auto transmissions are spotless inside. ATF is highly detergent, it is a closed system with no combustion taking place like in the engine. There just isn't the debris there is in an engine.

I think you should have it properly serviced with a complete fluid exchange and filter.

Originally Posted by snowsled7

Why not flush it? You might as well change all of the fluid right?

I have read the internet legend that a flush will somehow damage your transmission. My experience is with a Snap On transmission flushing machine, I have used it, and seen it used on hundreds of vehicles. I am not aware of a single one ever having a failure after a flush. Fluid flows through the trans as it would if it was running, no excessive pressures, no backwards flush. It is designed so that it can not possibly harm the transmission.

I think the root of this legend is so many people buying old vehicles with worn out automatic transmissions. They buy a car with a trans on its last legs, try a flush as a fix to a mechanical problem, the trans fails and they want to blame the flush. Fact is, the trans was cooked before the flush.

I have read the stories that claim sludge is knocked loose too gumming up the works. This is extremely unlikely as most auto transmissions are spotless inside. ATF is highly detergent, it is a closed system with no combustion taking place like in the engine. There just isn't the debris there is in an engine.

I think you should have it properly serviced with a complete fluid exchange and filter.

I agree with this assessment. There is a lot of urban legend associated with auto tranny service but my experience and that of a few knowledgable mechanics is that any type of service (flush or fluid/filter change) is beneficial IF DONE CORRECTLY.

The ATF change write-up sent by Steve is excellent. Thank you.
A few comments and questions:
Two feet of clearance between ground and sump pan would be nice for working space. I am thinking of using four floor jacks to keep the car level.
The Pelican Parts write-up estimates 45 minutes for the ATF to reach the proper temperature. This is because the transmission is heating slowly when not engaged.
Isn"t there a standard amount of ATF which should be in the transmission? And if that amount is put in after the sumps are back in place. why not run the engine with the transmission engaged and wheels off the ground
to speed up the heating of the ATF?
What is the purpose of running through the gears with your foot on the brake? The transmission is not moving.
Does this engage the pump to circulate the fluid?
Why would the fluid heat up at all, when nut under driving conditions?

One more question......what is the best brand of filter and gasket kit to buy. I am thinking of Meistersatz from AutohausazAz.

Originally Posted by Larrick

Isn"t there a standard amount of ATF which should be in the transmission? And if that amount is put in after the sumps are back in place. why not run the engine with the transmission engaged and wheels off the ground
to speed up the heating of the ATF?

There is a standard amount if you could drain the whole system. Most of the trans fluid is in the torque convertor. If you can't drain it, it stays in the system and all you can do is guess. You can measure what you remove I guess.

What is the purpose of running through the gears with your foot on the brake? The transmission is not moving.
Does this engage the pump to circulate the fluid?
Why would the fluid heat up at all, when nut under driving conditions?

With your foot on the brake and the trans in gear, the engine is running against the torque convertor. This will heat the fluid up more quickly. The convertor is like two fans blowing against each other in a fluid bath. The fluid heats when the fan on the engine side is pushing against the stationary trans side fan.

Seems to me that the $100-120 is costs to have the fluid exchanged at a shop would be a lot easier and cleaner than trying to do it yourself. Good Luck