Originally Posted By: HosteenJorje
I recently removed the OEM stat from my 04 Camry that had Zerex Asian Vehicle in the cooling system for the last five years. No rust on it or anything else. Doubt what you are seeing is rust. Why would only that component rust? Nothing wrong with Zerex Asian coolant.What's wrong is the outrageous price TMC asks for the OEM coolant which is probably made by Ashland.
I often read that the OEM coolant is overpriced ("outrageous" in your words), but I just don't see it. The Toyota red is $25 a gallon at my local dealer, and less if I email them first and get a discount. The pink is less of course, around $18. So for me it is $25 for two gallons of coolant.
I have used only the red since both my Toyotas are new and I can state for a fact that the internals of the engines, including the thermostats are pristine even after 300,000+ miles in my Sienna. I just put on what is probably the last timing belt and water pump in that engine and there was no corrosion, no deposits, no nothing. The thermostat in the ECHO failed about 20,000 miles ago (stuck open) and when replaced it didn't look at all like what the OP has pictured. It looked fine except that it wouldn't close.
If it were me I'd skip the TRD thermostat and use a regular "Toyota" one, and use the OEM coolant.