How to: Change Transmission Fluid ATF WS

It’s not heat that turns the oil black it’s gear wear. It has a differential in there. Lots of break in wear. It’s identical to the g2 platform with the exception of much higher power mgs.

I think it would have less break in wear as usually differential drives use much thicker gear oil better lubrication but instead use a D6 viscosity fluid.
The transmission is cooled by the inverter coolant loop but the fluid is
Not cooled exclusively they are more concerned about cooling the motors.

The transmissions on these cars are very well engineered. But like most differential gear drives high break in wear but after that initial trans fluid change it will show much much lower gear wear. If you plan on keeping the car for say 10 years years change it at 10,000 miles then again at 50,000 miles you will be good to go for the life of the car trans wise.

But break in wear is happening to other easily serviced systems too.
Especially the inverter coolant loop. Lots of break in contamination of that fluid to from the raw and large aluminum heat sink under the inverter.

Please go on YouTube look up WEBER AUTOMOTIVE PRIUS tutorial videos they do full dissections of all the Prius platforms taught by the Professor himself.

Very interesting.

 

Yeah it was likely looking pretty dark by 10K. Not ink, but on it's way, and a good time for first change.