Did I just get ripped off at the Dealer?

Yeah, I don't think you can really "flush" the transmission (no torque converter, right?). It's a drain and refill. To be on the safe side, I'd do two drain/refills with some miles (25?) in between. I've done the drain/refill myself and it's pretty simple. It's similar to a fluid change on a manual transmission. Drain the fluid out of the bottom, and fill it until it runs out of the fill hole on the top of the transmission.

I'll be damned if I can find the how-to document I used but it required about 4 quarts of ATF-WS, which I bought from a close-by dealer for about $7.50 a quart. Then you need to make or buy a funnel with a tube on it. You have to be careful to not accidentally drain the inverter coolant.

Here's the basic job: Reconditioning a Toyota Prius - Changing the CVT Transmission Fluid | NotPetroleum Blog The how-to document I used had more pictures including the one showing the right and wrong drain plug... just do some searching.

Scott

Edit: you probably don't need the torque wrench as suggested in the above link.. unless you've got one laying around. I think it's overkill. Just don't tighten the drain and fill plugs with an impact gun... use a little common sense, tighten but don't over-tighten.

 

Usually 4½ quarts so make sure to pick up 5 OOPS not sure what I was thinking. It is more like 3½.

 

The electrical properties of T-IV and ATF WS are the same. Every time I see someone say otherwise, I will gladly call BS on that myth. T-IV is the standard for Gen 1 transaxles, which also contain two motor-generators. To first order, all this stuff is just ATF. Whether or not conformal winding coating failure (i.e. a short in an MG) is caused by fluid oxidation or dirty fluid in general is a different story and perhaps one that will never be known outside of Toyota.

T-IV is not as good as ATF WS as a lubricating fluid, however, and so replacement should be done sooner rather than later, at your convenience instead of urgently. A drain and refill will suffice. I have never been able to get a full 4 quarts into one of these, usually it is more like 3.7-3.8.