40,000 Mile Service

[DR Z4]

Hi:

I have 65,000 km (40,000 miles) on my M roadster, and I am going to take it in for a valve adjustment. I have the BMWNA service interval guide, but what do you think are the things I should have done at this time?

For example, diff oil, tranny fluid, etc?
I'm not sure what I should and shouldn't be doing.

If I do change other fluids, would you recommend anything other than OEM?

I just want to take care of this car as best I can, and I feel like the the dealer recommended services I did while it was under warranty and CPO warranty were perhaps the bare minimum (of course I change the oil more often than recommended, etc).

Thanks!