Thermostat

Has anyone needed to replace the thermostat on a 3.5? I'm waiting in a dealership for them to diagnose it (still under warranty).

Seems like an odd part to fail at around 25k, but all the symptoms certainly point to it (doesn't get up to 200f, fluctuates while driving, giving code P0128).

My searching had lead me to believe thus is a very uncommon failure. Anyone here seen it?

 

I have only been here going 4 years, but I can say: I have not read one single thread of a bad thermostat was confirmed the issue.

 

^

Same, but doesn't mean it hasn't happened. Doesn't sound common

 

Not common but looks to happen. Wouldn't worry much about it. Should be an easy fix.

https://www.tacomaworld.com/threads/3rd-gen-3-5-won’t-get-up-to-operating-temp.754142/

 

Man I don't know how I missed that thread. My searching abilities have gone downhill..

I feel better knowing my truck isn't one of a kind haha. Hopefully the dealership doesn't screw around with the warranty.

 

Nawwwww...the search function is meh. Better just to type your question into google.

Welcome aboard!

 

If future searches lead anyone to here it was the thermostat. I had just bought the truck but it had 24K miles on it. It was under warranty & the dealership replaced it, but it doesn't look difficult to get to.

 

Great, thanks for following up! This info is valuable and it helps others just take min to let them know.

 

It's fairly common, they were backordered during covid, I had to wait 3 months for some.

 

I hate reading a thread explaining the issue your having with no resolution.

Yeah at first the dealership said they were on backorder and I might have to wait, but they managed to track one down.

 

Reviving this thread. Taco threw same code (p0128) over the weekend. Just scanned with my ODB and also surprised but nice to hear nothing major. I also have a 2020 MT, maybe we got a bad batch of thermostats. I preemptively scheduled a dealership visit before I scanned just in case. Thinking now I might be able to swap it myself.

 

Might be covered under 5 year 60k warranty

 

Thermostat on my coworker's '21 TRDOR failed right about 25K miles.

 

Forgot to followup on this. Dealer covered under the 3/36 warranty even though I was a month over it so that was nice. Rep said they've seen a couple of these recently.