A/T Transmission service - should we?

[Smolck]

Why is this even a question? It's like saying "should I bother changing my oil"? Why do people think an automatic gearbox is somehow exempt from wear, tear, heat, and filters getting clogged over time? Not to mention, when you do a filter change/trans fluid refill, you are only changing out about 30% of the fluid. You SHOULD do a true flush to get all new fluid in it, including what is in the torque converter.

People have this misnomer that you will "dislodge" sludge clogging the passageways and then have issues you didn't have before. What they don't realize is that the BMW auto valve body isn't like a 71 Oldsmobile valve body. The little balls and such that cause those problems don't exist in the BMW valve body.

The biggest issue is people don't use the right fluid when they re-fill it. Even though nowadays it is readily available online for decent prices. Face, it, you may spend $400 for a proper gearbox service, but it is a lot less than a new trans.

And of course BMW says it is "lifetime" fluid. And it is, it lasts till the transmission fails, duh. Ever notice the "lifetime" fluid came about around the same time as the "FREE" maintenance program? If you truly want your car to last forever, service it properly. If you don't want to keep it past 120k miles, then skip the trans service.

I change the fluid in my manual every spring and every fall (about 20k miles or so). It has 207k miles and still shifts like butta.

CHANGE YOUR FLUIDS! Autos need it every 30k MAX

[danewilson77]

It all just comes back to BMW saying it was "lifetime". That's why people ask.

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[ELCID86]

Shad, what are your thoughts on my son's car that only has ~15k on the manual tranny fluid, but it was last changed 4 years ago?

[Smolck]

Shad, what are your thoughts on my son's car that only has ~15k on the manual tranny fluid, but it was last changed 4 years ago?

Depends greatly on the brand fluid. I use RP Synchromax in the winter and I don't leave it in the car longer than 20k miles. If it is that, in your case, I'd change it after 4 years. I use Redline MTL in the summer (cause it gets so hot down here and I drive hard) and that is better fluid so I'd go 30k miles on it and feel safe.

Long answer to a simple question. Sorry about that. I'd say change it.

For the ZHP gearbox I'd also recommend replacing the factory torx drain plugs with normal hex head ones.

[ELCID86]

Depends greatly on the brand fluid. I use RP Synchromax in the winter and I don't leave it in the car longer than 20k miles. If it is that, in your case, I'd change it after 4 years. I use Redline MTL in the summer (cause it gets so hot down here and I drive hard) and that is better fluid so I'd go 30k miles on it and feel safe.

Long answer to a simple question. Sorry about that. I'd say change it.

For the ZHP gearbox I'd also recommend replacing the factory torx drain plugs with normal hex head ones.

Thanks. Will put it on the list of summer projects for his car.