How many miles on your transmission?

Those in the know seem to recommend drain & refill of transaxle every 60,000 miles. Did same on our 09 Gen II, never missed a beat in the time we owned it. Can't speak of longevity though, as we traded it in on a new 2013 Model 3 recently. You might say they gave me a deal I could not refuse.

Best of luck to you.

Ron (dorunron)

 

17, 500 on mine so far, running like a champ! no oil change yet.

 

So far transmission failures have been relatively rare and fairly random, judging by reports on PC. If your fluid looked OK at 95K, that would indicate it had been changed once before, as I changed mine at 35K and it looked almost black. Terrain makes a difference. Mountains, heat, and towing would all be reasons to change fluid more often. Those taxis lumbering up and down the steep SF hills all day put a tremendous strain on the innards.

 

From the readings I've done, I believe the transmissions hold up, it's MG2 that is failing. I don't even think the fluid changes has anything to do with MG2 failures.

 

My 2004 Prius is at 255k miles on the original tranny (ATF refresh every 60k miles).

JeffD

 

Changed trans fluid twice so far on my 70K 07. Getting ready to do the third any day now.
Used Redline D6 on both and pulled a UOA on every change. Posted above in the stickys under transaxle fluid analysis.

Coming up on 7 years running D6. Excellent UOA wear numbers.

 

At Lifespan/Operating costs - Prius Wiki, I have a link to 2 fas 4 u's 09 Prius which he took to 465K miles before trading it in.

Also there are links to Andrew Grant's taxis. His 01 taxi sounds like it went 329K km. His 04 Prius he mentions went 1.5 million KM before retiring.

It sounds like all of them were on the original transaxle.

 

312k miles on original trans on a 2004 prius. change every 60k now that I am out in dusty Az. In N. Calif. don't worry about it, maybe change every 120k miles. The 299999 thread has about a dozen people with over 300k miles with the original Trans.

 

I think that you'll find that for almost everyone here the number of miles on the transmission is identical to the number of miles on the car. Very few people have reported failures.

 

My first drain and fill was at 97K (03/16/12). The second was a couple days ago at 171K. I'll be following the "every 60K" guidance from here on out. Question, is it not true that MG's 1 and 2 are bathed in ATF WS? Isn't there also an inverter coolant loop through the MG's? Seems like I read this somewhere in all of these threads.

 

It is true that the MGs have contact with ATF WS. The inverter/transaxle coolant loop flows through the transaxle case. I suppose the heat transfer occurs via the transaxle case.

 

Mine failed at 153,000 miles. I had just bought it used. The original owner commuted long distances at high speeds in the Texas heat and never changed the fluid. I personally believe that if the trans fluid is changed every 60,000 like most on here recommend, these transmissions will last a good long time.

 

That and change the Inverter coolant also. That protects both the Inverter & trans. The huge cross section of pure aluminum heatsink in that coolant loop is very hard on the coolant. Very easy to do and very inexpensive. All you need is a gallon of Toyota SLLC found at the dealer for $20. It takes a few quarts. Good bang for the buck as you should see small mileage gain due to Inverter running much cooler.

The ICE coolant on the other hand last's much longer and can be changed at the recommended 100k mark.
But you can refresh it by just dumping the overflow bottle and the rad only. Very easy & fast. Your under there anyway. Do that a couple of times in a month and you'll have replaced quit a bit of ICE coolant and not have any air lock issues.

 

Ron, how many miles on your 2009 when you sold it?

 

Ron hasn't been on here for a while now. If I remember correctly, he was around 80k miles when he traded it

 

What are MGs?

 

• MG1, an AC motor-generator having a permanent magnet rotor,[7] used as a motor when starting the ICE and as a generator (alternator) when charging the high voltage battery
• MG2, an AC motor-generator, also having a permanent magnet rotor, used as the primary drive motor and as a generator (alternator), which regeneration power is directed to the high voltage battery

 

Closing in on 240,000 miles. Fluid changed twice. Getting ready for another drain/refill before winter sets in.