ATF Change

My thoughts exactly! ATF-4, Dextron 6, WS are rumored to be synthetic but it is all smoke and mirrors in my opinion because none of the cans say synthetic.

 

Exactly! If there was some unique electrical resistance required - which BTW since ATF contains friction modifier and seal conditioners to work with clutches and bands, would make ATF a POOR choice for electrical resistance - then Toyota would have made an oil just for the Prius CVT case

Considering that there is a sun/planetary gearset inside, a power transfer chain, and a diff, a GL-4 oil would have been far more appropriate. Such as this stuff

Mobil Delvac Synthetic Transmission Fluid 50

Which would offer better protection of gears than an ATF

I did an early initial change, at around 12,000 km, and the oil was already discolored. Since it was so easy to change, I did yearly changes every fall.

Despite putting on upwards of 80,000 km on the oil, subsequent cvt fluid oil changes, the oil drained bright red and looked as if it held up very well

I feel there are benefits to doing an EARLY initial change, not waiting until +30,000 miles before changing it. I was glad I did so, and if I get another Prius, will do so again

 

So which fluid did you use? Toyota or Mobil? Thanks!

 

I used the dealership WS. I could get a 4 litre tin can of WS (It was plastered with Japanese lettering, Made in Japan, etc) for $22

 

FYI for everyone that has their ATF WS changed at the dealer. For the first time since I started having Ema's ATF changed every 50,000 miles the dealership added a "Trans-Conditioner" to the drain and refill.

I always supply them with 4 quarts of ATF WS and never before had they left anything in the car. This time there was about 1/2 quart or more left in one bottle. A little investigation revelaed that a Toyota Part# 2150 described as "Trans-Condtnr" was added to the ATF drain and fill. This little bottle of conditioner cost $43!!!!!

Since I didn't ask for it I had my Service Advisor remove the charge from my bill. I am sure it isn't a bad thing to have done but really didn't want the $43 charge, lol.

Just wanted everyone to havbe a Heads Up.

Happy driving,
Chris

 

As a tag to this ancient discussion which nevertheless came up as the #1 google hit while looking for info on changing my own ATF:
ATF invariably becomes saturated with metallic particles, especially in a "maintenance-free" automatic transmission. It seems to me that such saturation would quickly negate the insulating properties of any special fluids, especially when metal shavings get wedged between exposed coils. The coils must be either isolated or very well coated themselves to resist such direct shorts.

 

The Prius does not have a torque converter automatic, nor a cone and belt CVT. It has a software controlled planetary gear set, where nothing ever shifts or slips. once the initial break-in wear happens, nothing further wears much.

My temptation would be to change at 30,000 miles 100,000 miles then every 100,000 miles. But that is just my opinion.

 

Ah, in which case, this info probably applies to my other post wondering about the safety of changing my ATF for the first time at 145k miles. Which I see I have answers to as I type.

 

Quite safe, no tiny passages to clog, no wear parts to slip