Nubo wrote: ↑
Sat Mar 23, 2019 12:34 am
As I understand it, most of the magic underlying the myriad of different ATF specs, has to do with friction modifiers. Since there's absolutely no shifting going on, I doubt if any of it matters for LEAF. That said, I know my doubts don't constitute facts and so I did choose the Redline D6
That's right basically. The involute helical gears aren't very sensitive to what level of friction modifiers are in the ATF fluid, something conventional automatic transmissions need for their specific clutch materials & pressures. The gear faces do squirm a little when hit with forces, but it's small rubbing compared to things like piston rings, cam lobes, AT clutches, all we don't have of course.
Viscosity-induced teeth drag has the biggest effect on Leafs for us, not friction modification. I wouldn't use any ATF fluid or GL-4 gear oil with a KV100 viscosity greater than 7 cSt here. Nissan Matic-S made by Idemitsu, who likely is the OEM supplier for Nissan, has a KV100 = 5.5, quite low compared to many DexronVI-rated ATF fluids out there which are about 6.2 or so.
Redline D6 is good, but I'm picking Amsoil Fuel Efficient ATF (ATL code) with an all-PAO GroupIV oil base for longevity, and viscosity is low enough at 6.3 cSt. Also GM's "Dexron HP" (Mobil 1 makes it I think) is excellent too, good for 150,000 miles in their automatic transmissions, and used in Chevy Bolts to go around 200,000 miles or so, advanced tech inside.
As an aside, I notice "LEAF" should always be capitalized like it was some acronym. Does it mean "Low Emission Automotive Future
"? Guessing. Some might say "low" should be "zero", but we all know the electrical grid ain't "zero".