Too late? Transmission Fluid Change 170k miles, New Prius Owner

Never too late, what about the egr circuit?

I would relax about the battery until you get a code, but start shopping now

 

Transmission problems due to not changing the fluid are rare on these cars. Changing it is probably good, but other maintenance items are more urgent, if neglected---engine coolant, and checking EGR status, for just two examples.

 

Changing the fluid is something you can do. 4 jack stands and a jack to get it up
in the air, and level. Very important. It's just a drain and refill. A 10mm hex head
and a 1/2 breaker bar, alway break the FILLER plug BEFORE the drain plug!
Then a hose and a funnel to pour the 4 quarts of Toyota WS fluid in.

If you get he Prolong system and run it though the whole cycles it should bring new
life into the hybrid battery. It certainly worked for me.

It would be a good idea to clean the whole EGR system, which includes the intake manifold's
4 small inport holes for the egr gasses. Spark plugs are due also, if they haven't already been done.

carfax is a 50/50 guess. I've read too many not so good stories about them.

I love my 2010 Prius with 305, 5XX miles in it!

 

It's never to change the transmission fluid on the Prius transmission. The warning on late transmission fluid changes has to do with automatic transmission using friction material that is worn with detritus in the fluid, There are no bands or clutches in the Prius CVT,

The only detritus in a Prius CVT is metal worn off the the gears which does not affect the efficiency of the transmission but results in more unwanted wear.

 

Transmission isn't going to break, don't worry about it.

Fluid change won't hurt, but don't freak out that it hasn't already happened.

A Prius is far more gentle to its transmission fluid than most cars, so it can last far longer without penalty.

As far as your battery goes? I probably wouldn't spend any money on reconditioning a 2010 battery at this point, just use up what's left and save your pennies for the next one. You could get some nice easy years out of it without ever needing to spend that money, but be ready all the same.

 

here's one video, there are many, and many threads here. make sure you do the intake manifold ports at the same time, they can clog and nothing else works even if clean.

watch

 

Don’t be too concerned about Carfax not showing some maintenance item. I maintained my F250 meticulously (through Ford Dealerships) and some of the items didn’t show up on carfax even from the best dealerships.

 

Hey OP, congrats on the prius.

But heres a cool thing you should know about any hybrid car with a eCVT transmission. They will NEVER break from not changing transmission fluid, ever. The only reason that happens to regular transmissions is because there needs to be grip to catch different gears. Hence they use clutch pads and they wear out faster from gritty transmission fluid and changing it can slush the grit around and cause it to slip.

Even worse, CVT transmissions which have a belt. That belt is delicate and made of numerous metal plates in a band. They constantly pull and any shaving particles in the fluid can cause destruction. Mostly due to overheating, but its inevitable for those transmissions to go out because metal belts can only pull for so long before they get warped on the microscopicle level till they snap or cant pull no more.

ECVT is all magnet. Electromagnetism. Like your blender, washing machine, powertools, fans, ebikes, etc. Dirty fluid or clean fluid, it doesnt matter. Its only purpose is to dissipate heat away to the radiator. As long as it HAS fluid, thats all that matters. If not, youll burn out the copper wires, as with any electric motor thats been overheated. But the prius has a fuse to prevent too much electricity from killing it like that.

My car had 300k+ miles and fluid was never changed. I changed it myself eventually, and its not the easiest thing because you drain and then fill from the overfill plug which is sideways. So youll need a long tube and a funnel or syringe. I put regular auto transmission fluid, whichever i found to be the cheapest. Doesnt matter, even engine oil will work, but i wouldnt try it. The viscosity does make a difference and so does the heat soaking properties. Id worry about if your headgasket is fine before anything else.

 

Change the transaxle fluid. If the brake fluids never been changed I’d look into that as well. Check EGR too: if it’s never been touched pretty a slam dunk it’ll be socked in with carbon.

more info in my signature.

 

It’s doable.

 

The ATF-WS fluid in there is a lubricant. It does have to keep the gears and bearings from wearing out. It also gets poured over the electric windings for the two motors to cool those off. It carries that heat to the aluminum case, where the heat gets transferred to the pink coolant, which takes it to the radiator.

The ATF-WS has to be a good lubricant, and it also has to not eat the insulating varnish on the electric windings. If the varnish gets damaged, a small short can start somewhere, and progress to a bigger motor burnout.

There isn't anywhere the Prius could have a fuse to stop that from happening: because the rotors are made with permanent magnets, once there is any short in the copper windings anywhere, there is a current loop right inside the motor itself any time the rotor turns. There's nothing for it but to replace the stator (or the whole transaxle). Gen 1 cars used to need that now and then. It seems to happen less in the later generations.

Some have suspected that if the ATF-WS is very old and chemically degraded, it could be more aggressive to the insulating varnish, which would be a reason for changing it. I don't know if that's really a thing or not. I changed mine.

 

Sure, run 90w gear lube in the Prius transmission. It doesn't matter.... because it's not there car.
It does NEED the correct fliud. It keeps the electric motors turning correctly, lubs the bearings,
protect the electric wiring around and in the motors.
It does break down over time and miles. Since it's very good fliud, it will last a long time.
WHY would you want to risk YOUR transmission with cheat incorrect fluid????
The fluid is not that expensive, just get the correct fluid, and amount, and don't worry about it
for 50,000 miles or so...

 

Ah i did not know that, thank you for the explanation. I have seen a few pictures of broken hybrid transmissions and they are all some variation of the copper windings burnt to brown. I believe earlier generation models. Not sure if this was caused by old or insufficient fluid or not, but hybrids generally tend to be problem free when it comes to transmissions. Hence the reputation on their longetivity and also the lack of transmission breaking posts.

Also to the other guy, i dont actually advise to put straight oil lol. Im only exaggerating to move the point home how undestructable these transmissions are. But i have used cheap ATF on my car and on the front it claims works on toyota hybrids in the small print. The car itself is cheap so im not too bothered if i break my car because thats an opportunity for me to go to the junkyard and get another transmission to replace with. Every junkyard i been to, the transmission is always still intact lol, only the engine and cat are missing which again further concretes the idea that these things wont fail for me

 

Transmission fluid needs to circulate to carry away heat as it functions 90w fluid will flow very slowly compared to WS. As such heat will be retained and heat causes premature breakdown of the insulation in the copper coils of the motors and degradation of the electronic components in the inverter. The life of the entire transmission and inverter is therefore shortened.

 

So, how did it go? Did the fluid smell burnt? Did gears start slipping?

My 2012 Prius almost have 170k miles on it and I've never even thought of the transmission fluid until now and I'm about to move CO to AZ towing a small load and panicking.