Coolant Flush Service Questions

There is no need to do a coolant "Flush" on a Prius. It just requires a drain and refill at 100k miles. You will need to do it every 50k miles thereafter if you use the super long life coolant.

JeffD

 

The thing to do is check your warranty and maintenance manual that came with the main owners manual. 100k miles is good for coolants and you will soon need spark plugs by the book. The dealer prices vary widely. You can also have most independent shops do it. The trick on the primary coolant is getting it all out.

 

The bigger issue is getting the air out of each cooling system by properly bleeding each one. Leaving a bit of the old coolant in each system is not a serious issue.

JeffD

 

For reference, I had the coolant drained and filled for both the ICE and inverter at our local dealer a couple of years ago on our Gen 2 Prius. They charged me $150 for each. That is probably too much to pay for the inverter drain and fill, which is much less problematic when it comes to getting all the air out of the lines, but I believe would be about the correct price for the ICE drain and fill (at least for the Gen 2, I would think your Gen 3 would have similar issues). I saw them working on the car for a couple of hours (presumably to bleed all the air out of the ICE cooling system), so I did not feel that I was ripped off.

 

One of the things I don't have trouble with on a gen3 is getting air out of the system. Generally the amount of fluid that comes out is measured and new of the same quantity is put in. It will register perhaps 1" high but running it in maintenace mode until flow starts is enough to clear the system. However getting all the coolant out and exchanged takes more effort.

 

Engine change IS in the sched, 100k or 10 year. In US inverter circuit is delayed to 150k, but doesn’t hurt. The term “flush” is torn used interchangeably with drain and fill; I wouldn’t read too much into that.

 

well it looks like my engine change way severely over due. Surprised it still runs!!! Going to find a jdm engine now.

 

,To add context, our Gen 2 had 211k miles when I bought it, with no record of either system's coolant ever having been changed. I put another 3k on it driving across the country before I had them changed. 80k miles later it seems to have suffered no ill effects, except that the Inverter Coolant Water Pump failed at around 275k, at which point the pump was replaced along with the coolant that had spilled.

 

Not in my part of the US. Mendel lives in a northern part of america, although after today he may not want to associate with us.

 

Toyota Canada says to change both coolant circuits at 160k kms or 10 years, whichever comes first. So last November, at 88k kms...

 

At first read yes, but follow the footnote (#3 IIRC), and you’ll see a contradiction: footnote says to delay inverter coolant change, to 150k miles or 15,years. Which governs, I think. That’s US sched. Including Nome Alaska I’d think.

From Toyota Canada the official stance is 160k kms or 10 year for both. AND: there’s a decal on my inverter reservoir, that says to wait till 150k miles. I emailed them, and their response was to ignore the sticker.