My EV had the highest temp. I am running Mobil 1 with a bit of moly added.
Not saying it is or isn't the lube, but in my case, I have the EV rear end 'sealed' a bit by all of the luggage, much more then anything else there. And the CARC units should have more area exposed to cool air.
Maybe.
The true test would be do do a certain ride, measure it, change the oil, then repeat the same conditions.
I must admit that I was surprised to see Docc in the parking lot using that rectal thermometer on everyone's rear and not even cleaning it from rearend to rearend. Sounds unhygienic to me.