Prius C Tranmission/Transaxle/HSD Oil Change

My mechanic told me the same thing, it can be dangerous to change the fluid on a high-mileage transmission. Then he looked at what type of transmission these cars use, and also noted that this is not a "transmission flush," but instead just a drain and refill. These two factors apparently exclude the Prius' transmission from whatever makes transmission flushes dangerous on high-mileage cars. Since a lot of folks ran tests on the fluid and concluded that it's best to change it for long-term ownership, I've done the same on both my hybrids.

 

What atf did you end up using? I want to do ATF, debating on using Eneos Eco-ATF.

 

I would use Toyota brand only, why try something else?

 

TOYOTA ATF-WS, it smelled different from other transmission fluids, almost smelled like brake fluid. I always stick to factory fluids, other than oil.

brake fluid. I always stick to factory fluids, other than oil.


Merged

I've heard that in a high mileage, (neglected) traditional hydraulic transmission the solvents in the new transmission fluid can break loose old deposits. Then when the transmission pumps the fluid around to shift gears and the like the particles gum up filters and so on. I'm interested to do research and find out if this is an issues with new electronic shifting transmissions.

 

This is probably the best thread on PriusChat! Thank you to everyone involved. Had I not stumbled on this post I likely wouldn't have changed my fluid until the 100k mark or later.

You guys are awesome. Keep up the great conversation!

 

What a great thread!
Reading the differing opinions and watching the flaring tempers as member disagree is fascinating.

This thread takes me back to "Vanagon World" on thesamba where owners can create a mountain out of a mole hill instantaneously!

Anyway, I'm new here and thought I'd throw in my 2 cents.

I am heavily involved with preventative maintenance (PM).
I am certified by NAARSO, National Association of Amusement Ride Safety Officials, a Professional group that pretty much tries to guarantee that any visit you make to an amusement park, a carnival and yes, even a ski area doesn't result in you dying from mechanical failure.

The entire thrust of the organization is fixing known failure items BEFORE they fail and preventing premature wear where possible.
I won't go into details, but keeping you alive is expensive and a LOT of work!

I spend my Winters fixing things that honestly are NOT broken!
Rebuilding engines, rewiring mechanisms, replacing bearings and shafts because they MIGHT fail.

If we have a failure in a system, you might die or be injured, the apparatus is now shut down which costs money to not only repair and get it uo and running again but it is costing ridership $$'s as well.

I am also a CPO, Certified Pool Operator, and the same line of thought prevails, keep the water healthy and able to ward off problems BEFORE it is polluted by someone with an infectious disease or an unsafe body condition even enters the pool.

Let's just say that I am a preventative service minded person.

I recently bought a Prius C2 ........ I Gave up my 2007 Pontiac Vibe to do so.
A Vibe is essentially a Toyota Matrix built by NUMMI until 2010.
This was the best car I have ever owned!
It never failed to start, it never stranded me on the highway (except for a flat tire once) and it performed flawlessly for 180,991 miles.
Part of this service record is due to maintenance being done BEFORE IT WAS NEEDED.

IT had a CVT transmission, the tyoe with clutch packs and a torque convertor.
It worked well but I was well aware of the 100,000 transmission oil change interval which I scoffed at and as a result checked my transmission oil regularly.
At about 50,000 miles I Pulled the dipstick and smelled burned oil.
Uh Oh!
I smeared some on a white paper towel and verified a brown color had developed.
I puchased a pan gasket and filter along with a case of Toyota Transmission oil and went to work.
I dropped the pan and pulled the filter. Luckily there wasn't a mine field of debris in the pan or stuck to the magnet!

I buttoned it back up and refilled it knowing that It still had a few quarts in the torque convertor that could not be drained.
To remedy this I changed the oil three more times in quick succession removing almost all traces of the burned oil that intermixed with the new oil.

I Then determined that from this point moving forward that I will change the transmission oil at roughly 30,000 mile intervals.
I am happy to report that the transmission worked fine and never again did I experience the worn out "lifetime" oil that I saw at 50,000 miles.

Just so you know, I'm also the guy that replaces corresponding light bulbs. Say a left tail light burns out, I replace the Right one too. They are Same age, probably the same brand and installed on the same day, the corresponding bulb has experienced the same number of duty cycles as the failed bulb.

Anyway........
I plan to purchase a magnetic drain plug and I will install it as soon as I can on my Prius C that only has 200 miles on it right now.
I WILL change the transmission oil every 30,000 miles to ward off potential damage.

Am I wasting my money? Maybe.

But I "waste" money everyday as a NAARSO official keeping YOU alive on your days off out having fun at water parks, amusement parks and carnivals.
I'll "waste" a little of my money and needlessly use up a little petroleum product ro keep my Prius trouble free.

Dave

 

2013 Prius C 2. My fill plug was on the drive side directly behind the half shaft. However the drain was on the driver side about where you see the drain plug in most of the pictures I see on the internet just on the opposite side. Both plugs were removed with 10mm allen/hex head socket. I could not find any information, pictures or diagrams that showed the drain plug on the opposite side. However, facing the driver side was the drain plug. I called the dealer in an attempt to insure that what I believed to be the drain plug was indeed the drain. The dealer was unable or unwilling to advise that I was indeed looking at the drain on the opposite side from the fill plug.

Has anyone found their drain plug on the opposite side from the fill plug on a 2013 Prius C 2?

I did change the transmission fluid. It was dirty. It was transmission fluid that came out. I am going to try and find a place that will analyze the used fluid. I will post results if I can find someone to analyze the fluid.

38,900 miles. Replaced the Trans fluid with Toyota WS.

 

I changed mine at 30,000 in my prius c and my full size prius. The oil must have a additives that makes it dark. I had a friend wreck his prius at 700 miles and it cracked the trans case and the oil was dark. People have sent oil in for analysis at 30,000 miles and found high amounts of silicone in the oil from the sealing silicon used. I changed mine again in 30,000 and it looked new. So I guess it's up to you as to what you want to do

Posted via the PriusChat mobile app.

 

Just changed Transmission Oil change at 113K. Drain Plus under Driver seat and Fill Plug on Passenger seat.
Oil was real Dark..

 

2013 Prius c Two

 

Just changed mine at 55 500 miles - as others have found, very dark, almost black in colour. Nice easy job - biggest pain is getting the car up and level.. Used genuine ATF WS - managed to find a dealer online selling it 30% off + free delivery, so cost £40-00. Worth it for the peace of mine. I'll probably do it again at 100 000 miles.

 

Hopefully Mrs. Kingsway didn’t see her Pyrex matriculate to the top of the Prius .

Sounds like a good idea to change the fluid out.

 

There are things a lady does not need to know! It is spotless and back on the shelf as I type....!

 

Just preaching: it's probably been looking like that for some time. I changed mine at the one year mark (around 15K kms), then 3 year mark, then 6 year mark. Each time it seemed ever more pointless. The first change was by far the darkest.

 

Very informative. Thanks.

 

Changed the Tranny Fluid on my 2015 PriusC recently, mileage was 87Kmiles +, almost 88Kmiles. Old Fluid was very dark in color, no chunks, seemed to be fairly clean. New fluid is Valvoline synthetic ATF. I figured I should change the fluid as we have just paid off the car, need to make it last forever....

 

Have you seen the Owners Manual warning, the one about (paraphrasing) “anything other than Genuine Toyota ATF WS fluid may ultimately damage the transaxle”?

if you’ve got a pdf of the manual search for “ATF WS” will find the specific wording. It’s the one time Toyota gets completely emphatic about a fluid; not sure why so many choose an alternative, in light of this.

 

YES, I have observed the Toyota statement about transmission fluid. I have examined the fluid Toyota sells but does not manufacture. I have in the past engineered on US Nuclear powered submarines and am well aware of the requirements for gear boxes with gears similar to those in the PriusC transaxle (as well as two three phase motor/generator assemblies). We also had some pretty technical components on those submarines. I determined that the Toyota WS tranny fluid was okay stuff. There are a lot of pretty good lubrication formulations out there. I chose a formulation that is suitable and affordable.

 

Me too.

my credentials: I’m just bright enough to take them at their word.