Transmission Fluid Change

Drain and fill at 100k, then every 50k interval. There is no screen/filter/torque converter, relatively easy diy as shown in the following video.

OEM is best unless you feel the need to use non-OEM atf.

The Prius doesn't have a traditional transmission, so a "flush" is a attempt to extract additional $ from owners. You can only drain and fill. It's as simple as that.

 

The Prius transaxle is a far cry from a traditional automatic transmission, more akin to a manual transmission. A simple drain and fill will replace about 90% of the fluid. Stick with Toyota ATF WS, and do it asap.

 

Yup! No screen. No filter. No torque converter. No flushing.

The Toyota ATF WS is the standard. Some people will try to find substitutes, and there are other brands that work, but it's just not worth all the research or the risk imho to use other stuff in there.

There is debate as to if and when to change the fluid. One school of thought it to change it quite early to remove whatever manufacturing lubricants and what-not that could be lurking in there along with metal fines that come from gears breaking in. Others say to wait till 60k, 100k, and various other distances. But it is popularly accepted that changing it is a good thing even though very few Prius transaxles ever fail.

 

I'd recommend a first change around the one year mark or 10K miles, another around 60K miles, then maybe that's it for the duration.

The Owner's Manual is pretty admanant: that using anything other than Genuine Toyota ATF WS may damage the transaxle.

 

Thank you so much! I was told the very same thing about needing a flush by the dealership when I took it in for routine check up and I've read a lot of conflicting information online about the "flush." The dealership quoted me $300 and when I called various repair shops, they quoted me around $200 for a flush. Quick (maybe dumb) question, do Priuses require transmission fluid or oil change before the 100k mark?

P.S. I'm grateful for forums like this b/c these dealerships and repair shops are just eager to rip you off. Example, the "airbag off" light went on when my mom took the passenger seat recently, and when I called the dealership they told me it would cost $300 for them to "poke around and figure out the problem." Just before taking it in, I did a google search and it turns out that if the passenger weighs very little, the airbag off light will go on. So I tested it by having someone heavier sit in the passenger seat, and presto! The airbag was reactivated. So thank goodness for the internet and thank goodness for forums like these!

 

(^ From the post above yours. This is purely from the colour of the drained fluid I've seen. I've done 3, the first VERY early, around one year and 10K miles, and it was by far the darkest.)

I use the air bag off light as justification to send (lightweight) grandkids who want to ride "shotgun" to the back seat.

 

Yikes!!! I'm in the wrong line of business. I could be rich!!

There is no flush needed or possible for the Prius transaxle.

I just bought four quarts of Toyota ATF-WS and two crush washers yesterday from the dealer for $49. I plan to change mine next weekend, weather permitting. The change isn't in the service schedule, but I think it's a good idea to change it at least one time once the car is well broken in. At 34k miles, I'd say mine is ready.

 

One reason would be, if something like motor oil was accidentally poured in. Honda has a technique outlined in the Shop Manuals, and it's dead simple, and this is for conventional automatic transmissions, where you're only changing maybe 50~60 percent:

Drain and fill. Drive about a km. Repeat twice more.

 

Yeah, that's a special situation. But I wouldn't call it a flush. More like multiple rinses. A flush implies to me a continuous flow with some pressure behind it.

I guess, with the right fittings, you actually could do a sort of a flush, but I don't know how effective it would be since the drain and fill openings are so close to each other.

 

As with many (but not all) things ‘dealer’, that’s a pure wallet flush.