Are there any tricks to changing the thermostat in a 2008 FlexFuel Tahoe with the 5.3? I found that on my 99 2 door that I had to fill it with coolant with the old thermostat out and when the fluid reached the top of the intake, I would put the thermostat back in before finishing. By not doing this, I had issues getting the fluid to flow. Is there anyting like this on my new Tahoe or is it just drain, replace thermostat and replace?

 

why are you changing the thermostat on your brand new truck?just wondering

 

One of the first things I have always done is to change the thermostat to a cooler one. My 99 Tahoe ran a 180 degree thermostat and at 140,000 miles still did not smoke after being started after sitting for a few weeks. I just like to cool them off a little from the 195 that comes stock. No baking the internals at 210 all the time. It also helps with trans temps while towing which I do a lot of. So, back to the question, has anyone changed one on a 5.3?

 

Not a good idea w/ the NBS as the whole system is set up to run at 200*F. If tranny temp is a concern, then put on a cooler, either the one that comes on the HD pkg or an aftermarket one.

 

I am fairly sure engines run 200-210 for a reason, between oil temps, emmissions issues, etc...

however if you really want to do this, I would imagine you just swap them out.

Id wait until the 5 year 100,000 power train is up however.... or at least the 3/36...

I'm not touching a thing until my 5/60 is up!