I can only speak of the my experience with the M62/5 cog trans.

Lots of towing (even a 7500lb boat & trailer, with 5 passengers and cargo, from northern PA to south NJ. Overloaded for sure).

Did 4 drain/fills with a filter change during the 3rd one, this was done at 103k miles. I even used the Castrol Import Multi Car Syn (meets the LT71142 spec, Bentley shows this as an acceptable fluid). Many here said the trans would fail soon after.

Over 100k miles later, I can safely say those posters were mistaken.

I can say the TC has not held up as well as the trans, I have the toc-toc-toc sound under acceleration. Will be replacing the TC chain soon.

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'03 X5 4.4 Sport, last of the M62s (8-03 build date)
I believe in deadication to craftmanship in a world of mediocrity!