Originally Posted by bcredliner

There are strong feelings on to change or not to change. The vast majority of the time the not to change contingent bases their opinion on the BMW statement that the fluid is for the lifetime of the transmission. As noted, there is often mention that it will cause problems.

The change folks base their opinion on fluid degradation.

Changing the fluid and filter is an easy DIY and having the capability to take the temperature of the fluid is not critical. As long as the fluid is full, which means there is a small steady stream running out of the fill hole after the transmission has been filled and also after the vehicle has be cycled through the gears and the vehicle is driven but not hard for a few miles and then the fluid is topped off it will be fine.

The filter is completely separate from the pan. I dot think there is any reason to use other than the proper ZF fluid.

If you decide to change the fluid, how often is up to you. My interval is every 50,000 miles.