HRTKD wrote: ↑
Sun Oct 06, 2019 6:06 pm
Oilpan4 wrote: ↑
Sun Oct 06, 2019 4:37 pm
Do we know the matic s doesn't have these friction modifiers?
None of the ATF fluids I've worked with in a DIY capacity have had friction modifiers. The only fluid I've worked with that sometimes has the friction modifier built in is a gear lube designed for a rear differential. In that case, the gear lube explicitly is labeled as having the friction modifier.
I don't think there's any way to know unless Nissan (or others) revealed their ATF formulation. A friction modifier for a limited-slip differential is intended to avoid chatter by reducing
friction in the clutch pack that conventional diffs lack. But auto transmissions have multiple clutch packs. You can buy a friction modifier supplement for ATF to reduce converter lockup chatter or potentially soften hard shifts in an AT that you're not quite ready to rebuild: https://www.lubegard.com/products/black/
Since there are no clutch packs in the Leaf reduction gear box, friction modifiers are irrelevant as some others have noted. (Which is also true for the differential inside the transaxle of nearly all front-drive automatics.) Nissan presumably didn't want to formulate a new lubricant for the Leaf, so they took the most suitable product off the shelf. No need to overthink this one, just run the OEM ATF or a compatible 3rd-party product. Presumably, Nissan designed the box for minimal friction loss and an acceptable lifespan with the viscosity and and other characteristics of ATF. Gear oil is much thicker (higher viscosity) than ATF, which would undoubtedly affect energy efficiency.