DeeBee3

On the 04-06 330's Toyota calls for Type T-IV and after 07 they recommend WS. All models use the same U151E or F transmission with software being the only updated component.

That said, how many of you own a 330 and use the lower viscosity WS fluid? If so have you had all the applicable firmware updates as well?

MattRX

I am curious about this as well. The internals of the two trans did not change in 07, I searched every part number and couldn’t find any differences. I’m guessing that’s the factory fill and they just recommend you stick with it.

DeeBee3

Yeah that is what I assumed as well. Toyota switched to the WS fill around that time for all models (except CVT) but the two fluid are very different. Type T-IV has a kviscosity at 100c of 7.3 while WS is 5.3 so I'm assuming that there had to be some sort of calibration update specifically for the solenoids to crossover properly between gears. I'm sure they compensated with the fluid AP as much as possible but the viscosity differences are to great to just work as is.

Felix

Valoline's Maxlife trans fluid works w/ both..........

DeeBee3

I've been down that road. I grabbed two gallons of Maxlife when I first got the RX and did a pan drop/filter replacement then another drain and fill with all Maxlife. While it does "work" and admittedly shifted very smoothly it had alot of slip under heavy throttle. I have techstream and a mongoose so I'm able to reset the ECU/ECT memory when swapping fluids out to give it a fair shake but the Maxlife is missing something in the AP that provides grip. I've since swapped for straight Amsoil SS ATF and no more slipping. It's not as smooth or fuel efficient either though, and that was the motivation for this thread.