This is all great advice that should be followed but it doesnt guarentee your automatic will last long. I'm probably the only one here that rains on everyone's parade, but BMW automatics, eh.........not so reliable in the first place. You might get lots or little mileage whether or not you change the ATF fluid. (Of course, doing so shouldn't hurt the tranny, so why not)

Damn, now you've got me thinking. Why would that be? The new fluid causes the transmission clutches to grab better adding stress to the parts? The change causes deposits that were settled to disburse? Any ideas? I was going to change fluid but until I know more, I'm not going to mess with it. Thanks

The new fluid has no impact on the clutch packs except that the new friction modifiers in the fluid will return the fluid to the same characteristics as when it was new, if those friction modifiers had been depleted. The reason is the deposts that had settled, are stirred up and tend to block very small passages in the transmission valve body. They can also affect any micro-sensors. If a valve or sensor is not operating correctly, a clutch pack or band will tend to not engage (slip). That causes very rapid failure due to overheating.

The above is why I won't change automatic transmission fluid. I see no reason to mess with a transmission that is functioning well. I agree with checking the fluid level if there are any obvious signs of leakage, but apart from that, run it until it breaks. It will break, no doubt. It won't last forever. I just don't think that the failure point has a correlation with not changing the fluid, while I have seen a correlation with changing the fluid (for the reasons that The Cleaner cites). My experience with this is not with BMW automatics, but then these are not BMW automatics, so I think the comparison is valid.

I'm with JCL and TheCleaner...

unless one is doing hours of torturous off roading weekly,
driving in Dakar, or towing houses, I'd pass on the auto
tranny "drain". The orig. fill is prob. a syn or semi-syn, and
that orig. lubricant will outlast 99% of the time most here
will own their X, or that X will driven by anyone, in total.
BR,mD

Hi,

Thank you very much for your answers. However,now i'm even more anxious about the automatic transmission oil change :((

I bought the car 2nd hand and i don't know the history of it..it probably never had an automatic transmission oil change.

MOST IMPORTANT:
How do i check the final level of transmission oil if replaced?
At what temperature should the final level of oil be checked? Hot or cold?

Regards,