lexus-is2

My 2006 IS250 has 155k Miles (not KM) i'm still on original stock thermostat and wondering if anyone with high mileage IS250 has had to replace their thermostat yet? I'm thinking to replace it just as a precaution as I will be doing a complete coolant change soon.

Last year my car experienced overheating and it was due to the pressure cap becoming faulty. The valve inside the pressure cap had broken off. Unfortunately it happened at the worst time as I was on a European road trip. I'm planning another road trip this year and before it my coolant is due a change. So i'm wondering if it's common for the thermostats to fail and if so maybe I should replace it as a precaution.

synrgy350

I replaced my is350's thermostat at around 145K. It functioned normally and was not causing problems, but its good to do it as a precaution. Our engines are all aluminum and overheating it can warp the heads. Didn't take more than an hour and a half and the part was only $90 or so. Good luck!

lexus-is2

Is there a DIY out there?

synrgy350

I used to have a PDF but I can't seem to find it at the moment. The thermostat is in the very front of the engine, across from the coolant bottle. It has 5 bolts which hold it in and a few coolant hoses that need to be removed. Once you take the plastic cover off the housing area, you'll see what I mean. The thermostat is an all in one unit which includes a housing. If I can find the PDF I'll post it here.

lexus-is2

Thanks synrgy350, that would be awesome. Is there any kind of gaskets or seals on the thermostat? wondering if there is, I would need to get new ones too

I went on ebay and searched for the thermostat to see how it looks, i've come across the following picture, but only seems to have the one big hose connection and 3 bolts as apposed to the 5 bolts and few coolant hoses you refer to.



Thanks

synrgy350

That looks like the right thermostat type, however, I remember there being more than 3 bolts, although it has been a while since I replaced it. I would also recommend going with the genuine toyota thermostat, as it isn't much more expensive. Good luck!

lexus-is2

Did you replace the hose clamp? When i changed my throttle body a year back and disconnected the hoses. I reconnected the hoses and put the original clips back on after that i pulled at the hose and it came off so got worried and replaced with jubilee clips. Actually everytime i've tried to reuse stock clips its always been a failure. So wondering if I should replace with Jubilee Clip.

synrgy350

No I reused the clips but the ones in my car seemed to be in good condition. If you're worried I would order new clips at the dealer, they should be cheap.