[JHZR2]

I dont know, when I put in my 2011 135i, it says D4.



And from the redline product pages, first, in the gear oil for MTs, only D4 is listed.

Then, from the D4 product page:

Also used with manual transmissions and transaxles like T-5, T-45, T-56 and late-model BMW

While on the D6 page:

exron VI fluids can be used where Dexron III fluids
were previously recommended (with the exception of some manual transmission applications, our customers report).

Also see my GM tech bulletin I pasted above. IMO the jury is still out about the Dexron VI type chemistry being appropriate for MTs.

Unfortunately for much of this stuff, you dont see the real effect of decisions for tens of thousands of miles.

Though Dex VI is more shear stable, I personally would want the added viscosity protection of a higher viscosity from a dex III fluid, which IMO is already fairly light for a gearbox.