2014 Prius C Transaxel oil change

How to: Change Transmission Fluid ATF WS | PriusChat

I followed that guide, except I just used a long length of vinyl hose to refill. A pump would probably be easier w/o the risk of the hose popping out, and it's easier to keep an eye on when the transmission is full (overflowing). I also used two new crush washers on the plugs, which are P/N 90430-18008, as replacing used crush washers is always best practice. You can get 4 quarts of ATF WS + a 10 pack of washers on Amazon for ~$45...not sure about dealer price.

Wish I hand't accidentally dumped my shot glass sample of old fluid on the floor. It was very, very dark red after only 35K miles. Much to my surprise, the transmission seems smoother after replacing the fluid. As with a traditional automatic, it was starting to feel grabby in hot weather crawling through city traffic. Not sure why that is, or if I was just imagining things.

 

Zen, you've got me wondering if I should change the fluid in my C. I'm just about to hit 23k. What is the recommended interval for that change?

 

If it’s like the liftback, it’s not mentioned to be changed.

I did our 2017 RX450h trans axles at 6800 miles and the front transaxle had a film of metallics adhered to the magnetic plug .

Glad I did it and when we replace our 2010 liftback at some point, the next Prius that replaces it will also get the same treatment .

 

As with most late model vehicles, there is no scheduled interval by the manufacturer because the original fluid will go to the end of the warranty, at which point the manufacturer doesn't care. The dealer will be happy to schedule an appointment for a replacement transmission after that though!

30K mile intervals seems prudent to me. Just not worth skimping $35 in fluid + $2 in washers + 30 minutes of time to keep the transmission happy for long term owners. If you synchronize it with a 5 or 10K mile oil change interval, then it's even less time.

 

I asked my dealer how much this would cost and he very nearly refused to give me a quote on it... surprisingly. I leaned on him a bit about it and he finally came up with a price of ~$200.
He kept emphasizing that it isn't necessary on these transmissions. I just rolled over 100k and will do it for the first time here shortly... I need a free weekend to do it.

 

That's too much, and makes you wonder if they even know what they're doing. Unfortunately I don't have a Prius c Repair Manual, but I'd speculate the procedure is very similar to 3rd gen Prius (attached).Take a preliminary look, see where the fill and drain bolts are. I would speculate you need:

1. 4 quarts Toyota ATF WS

2. Fill and drain bolt replacement washers (Not do or die, but if the parts department can find them I'd get them. If it's similar to 3rd gen Prius the two washers (and the bolts) are the same.

3. Some sort of funnel with 3~4 foot hose extension: start long, and trim to suit when you use it. Save it for just that job, to avoid contamination.

4. Ratchet wrench socket with 10 mm Hex drive (male). Stanley sells a set of these, with 10 mm size the largest.

5. Torque wrench (3rd gen torque spec is 29 foot/pounds). (You can wing it, but torque wrench is the way to go, say a 3/8" drive.)

6. Solid, long handle ratchet wrench or breaker bar. (just makes life easier, the fill and drain bolts can be a little stubborn to break loose. Start with the fill bolt, just in case...)

7. Equipment/method for safely raising and levelling the car. When filling, proper level is achieved by filling (with the car level) until the fluid starts coming back out, so reasonably level is mandatory.

Again, attachment is excerpt from regular 3rd gen Prius Repair Manual:

 

Yeah, I laughed and told him it was a 30 min job if I were to do it... even less for them. I suspect he just didn't want to do it, for some reason... but that was honestly the reason I was asking is because I didn't want to do it.