Coolant fluid change procedure

Just broke 65K miles and would like to change my coolant as more of precaution than anything else. I can't seem to find a good writeup on how this is done. I don't think I need a real "flush" but would feel good doing a drain and fill. Has anyone done this yet on the 3rd gen? Are there any guides that I missed?

 

I haven't done it to my 3G yet, but I did on my 2G. Most cars are pretty much the same. You need a couple drain pans and coolant (suggest premixed). Make sure the engine is cold and open the radiator cap and reservoir cap. Finally, open the petcock on the bottom corner of the radiator and 2 on the block and let it drain. Close the petcocks. Fill the radiator slowly to allow air to escape first, then the reservoir. Close both. Run it until the thermostat opens and check everything again and top off. If you have higher than usual temps, you probably have air in the system. I never had that problem but I believe you open the thermostat with the radiator cap off to purge it (starting with a cold engine). Big thing to remember is the radiator is pressurized but the reservoir is not.

 

I doubt it's needed for this vehicle but if you're doing a lot of coolant changes look into an airlift. I got one for my 6.4 diesel then couldn't live without it. I did work in a shop for a long time though so I got my money out of it.

 

Thanks. That sounds simple enough. I'd read a few things about the correct order of things being necessary to avoid air in the system.

 

If it's easy to get at, putting a new thermostat in and putting a new radiator cap on would be cheap insurance. I'd use Toyota parts only.

Also, when running it after filling it, run the engine up to about 1500rpm with the heat on full blast till you have heat come out the vents.

 

Yeah it's not real bad. Just make sure you have enough drain pans before you start! Also, don't run it without the radiator cap on unless you have to purge. I will edit my first post for clarity.

 

Did the job today. Took about 90 minutes start to finish. The fluid that came out looked brand new. You say there were two drains on the block? I only found one, plus the drain on the radiator.

Factory service manual says the whole system takes about 2.25 gallons, but I was only able to drain out about 1.5 gallons and that's what it took to bring the fluid back to the correct level. I know a lot of guys say to flush with water. I probably should have, if i wanted to remove that remaining .75 gallon, but being as the fluid looked so new, I'm not overly concerned with it. Next time, and for anyone who reads this though, if you want to remove all the old coolant, you will need to flush with water, despite that step not being mentioned in the service manual.

 

If there was another 3/4 gallon of fluid that didn't come out, it is because some section of the block didn't get drained. You cannot flush water out with more water.

 

That makes sense. I'm really surprised how clean the fluid looked, and I'm at 65K and have a lot of mud and water crossings on those miles. Probably could have made it to 100K easily.

 

The maintenance manual in the glovebox recommends 100K.

 

The OEM stuff is probably rated to last 100k-150k miles. Most coolant is these days.

 

Dang, you're right. All this time I thought it was part of the 60K service. Oh well. Only thing left for me now is spark plugs. Did gear oil, transmission fluid, transfer case fluid, and now coolant. Quarantine got me busy at home...

 

Yes as soon as it started draining and I saw how pink it was a had a feeling I was doing unnecessary work. Oh well, truck will probably rot away from NY winters before I put another 150K miles on it.

 

At least it's all out of the way.

 

Keeps me busy and out of trouble. By the end of this quarantine I'm gonna have the cleanest house in the world, and will probably rebuilt half the truck. Otherwise, the boredom will get me crazy

 

I know you are finished, but when I did the coolant drain and fill on my 2nd gen, there were 2 block drains (one on each side) with one of them being VERY hard to find. I know you have a 3rd gen, but just saying maybe you missed one of the block drains? And on the 2nd gen, I believe the manual only recommended a drain and refill with 50/50, not a flush with water. I wouldnt be surprised if the service manual stated the same for the 3rd gen but not sure.

 

No I think you're right the more I read about it. The service manual shows one drain on the diver side, and when I couldn't find it I went to Google, and saw how to find the one on the passenger side and I thought it was an error or misunderstanding so I continued on. But I do think there are two plus the drain on the radiator, which would explain why it didn't completely drain as much as I thought it would. But yes, service manual doesn't say anything about water, just a drain and fill and that is why I followed the procedure I used.

 

I did my drain and fill today. I did the same as you, couldnt seem to find the drivers side drain so I just pulled the passenger side. I got about 2 gallons out. I feel fine about it but if anyone finds the drivers side drain please post up pics!!

 

ChrisFix has a great video:

https://www.youtube.com/watch?v=s--5ft5YiHg

 

No, I think YOU'RE right! The 2gr-fks FSM schematic is very confusing and there is definitely not a drain cock next to the engine oil fill spout like it seems to suggest there would be. Maybe its bolted under the alternator, but since the FSM only ever mentions one cylinder block drain and doesn't specify which side its on, I believe the schematic is showing us x-ray vision from the driver's side to the location of the drain on the rear passenger's side of the block.