Thermostat Replacement

I have a new OEM thermostat from Aisin. My 4Runner is approaching 200k.

Engine is running fine except for some weird ticking sound. Existing thermostat still working good but plan to swap it with a new one when I change the pink coolant fluid. Using OEM Toyota Pink for that, as usual.

Should I replace anything else with the coolant system such as hoses/clamps or water pump? I did a quick visual inspection and I didn't see any obvious cracks but obviously a bit of wear on everything.

 

First, run a vacuum on the system and see if it holds pressure.

I would replace the hoses if they are showing any cracking, bulges, or feel really soft. If the water pump is not leaking or showing signs of failure, leave it be.

 

Water pump for sure!

 

Okay.....one says replace water pump and one says no.....

 

Runner is approaching 200k miles and poster has not indicated its ever been changed? Its their money they can spend it how they like but that would not even be a question for me... plastic does not last forever

 

I'm at 254K and have a thermostat, water pump, and radiator standing by in my basement. They know the call is coming eventually, either b/c something breaks or I hit my next coolant change at 280K, at which point I'll do it preventatively.

 

Assuming this is the V6 engine, the "weird ticking" could be a failing/worn timing chain guide. Something to think about at least.

Could also be an exhaust leak. Dunno if the V6 manifolds have the same issue that the V8 do with cracking.