Thermostat Replacement

Was planning on replacing my thermostat at the end of the summer as preventative maintenance and was told by a dealer tech there is a special way of bleeding the cooling system on these new 3rd gens. Does anyone know if there is anything different? Or should I just swap it out and jack the front end up with my coolant funnel and massage the hoses for a bit and run it till all the air is out and it cycles with the heater core flowing? I’m assuming it’s the same as I have been doing for all these years but just wanted a second opinion. Also on the V6 I haven’t looked to see where the housing is for the thermostat but I’m assuming it’s straight forward like most Toyotas, anyone know how difficult it is to access?

 

Why would you replace the thermostat on a 2020? How many miles do you have?

 

Not as straight forward as the good ol' days.

 

Agreed, I wouldn’t consider a replacement until 150K, at which point replace hoses and belt also unless you encounter cooling issues. On my 2nd gen I replaced all this, and rad cap and idler bearings, at 100K, and they looked good. Same for the Lexus ES350. Just replace the coolant at 100K and the rest will be good till at least 150K. At 100K, you can remove the belt and inspect the pulley bearings and belt for excessive wear/tear.

 

Not something that is necessarily a part that you would replace as part of preventive maintenance. When they fail, they fail. The one that is in there now is likely to last as long as a replacement.

 

Thank You for the links, also I get it will probably last a very long time but when doing preventative maintenance I always weigh the cost and time it takes to replace more than anything. Knowing it’s a simple and cheap process I plan to do it every 3 years when changing out all fluids in the truck including coolant. I live by the moto if I’m already in there I might as well change it out if it’s cheap.

 

That is your time and money, but I feel compelled to point out to others how wasteful this is. Money-wise and product-wise. Coolant is generally good for 100K, and there are coolant testers you can buy to test the coolant so you can know exactly when it starts to lose it’s effectiveness so you can replace it accordingly.

To answer your question about bleeding - if your 3.5 is similar to 3.5 in our 07 ES350, there will be a bleeder valve on the intake, near the oil filler cap. I’ll check our ‘18 RX350 later tonight, I believe the 3.5 in it is same as yours.

 

I have a 2019 that has been throwing a thermostat code, the cruise shuts off and check engine light.
The truck is not heating like it should so i will be swapping out the thermostat this weekend... ish.
I would have done this without the code and the inconvenience of freezing my ass off in the dead of winter.
Really didn't need Toyota to shut off one of my favourite things about my Tacoma, adaptive cruise.
What a PITA.
Leave it to the imagineers.

 

Get the trd 180° thermostat.

 

Installed the 87°C Thermostat which is 187°F version you are speaking of.
I opened the radiator drain, about 4 litres drain, removed the spring clamps with a decent size pair of needle nose.
I left the sensor plugged in, its easier to remove when the housing is removed.
Copper antisieze on erything.
The heat feels extra nice after freezing my arse off for an hour doing the install.

 

I had a tundra that was 19 years old, and i never needed to replace the thermostat, or the coolant in nearly 300k miles.

 

I also recommend removing the drivebelt if you have time, the coolant can wreck older belts and it will squeal. No matter how much you drain the t-stat always has more to puke out.

 

And mark orientation (numbers in / out) so it minimizes squealing.

 

I managed good enough without removing the belt. I ll remove it when and if it starts squealing.
The belt actually helped me catch one of the bolts twice when my big sausage fingers had trouble finding the hole.
Bolt landed on the belt and trapped it before it disappeared into the abyss.

 

Hello all, my 2020 tossed the coolant low temperature code. Engine light on, cruise not working and remote start not working as well. Just received from Toyota the new water inlet/thermostat. Hope this fixes the problem. 48 000 miles seems early for such a failure.....

 

Been getting the same code. I’ve reset it a few times because I was having issues with the front sensor and it will run for a month or two without issue.

now that it’s getting warmer I’ll probably go ahead and replace the thermostat and/or sensor.

 

Mishimoto makes a coolant vacuum purge and fill kit that makes bleeding super easy. Kit is like $50

 

I have 2018 tossed the coolant low temperature code at around 70K. Engine light on, cruise not working. Just received from Toyota the new water inlet/thermostat. Hope this fixes the problem. dealer ask for 1500 for replacing the thermostat, that is BS, I am going to DIY. my taco is not reliable as I heart....