Originally Posted by Rogue

A 180 T-stat is useless unless you have the PCM code changed to match it. Either get the stock 195 T-stat or get a 180 T-stat along with an aftermarket PCM like INTENSE offers.

Originally Posted by BoneZ

The 180* t-stat will still try to maintain 180* coolant running through the engine by opening up at 180* instead of 195*. All the aftermarket PCM will do is make the fan come on sooner. Therefore, a 180* t-stat will not be totally useless.

Originally Posted by imidazol

If the digital gauge is reading 150 degrees you're probably collecting a lot of unburned stuff on the walls and into the oil. It'* not good.

You can drain a little coolant out of the radiator with a siphon hose,
remove the two bolts holding the thermostat housing on at the end of the upper radiator hose- I don't even remove the hose from the metal housing,
remove the thermostat with it'* rubber ring that seals it
replace with a new GM Delco which will come with the rubber ring, IIRC
be sure to put the pellet end into the upper manifold like the one you take out was
carefully thread the two bolts back on being careful not to cross thread (I did)
tighten to about the same as the ones you took off
refill the coolant into the radiator
replace cap
run motor to heat up
after bottom radiator hose is warm (after a good drive) rev motor to 2500 rpm 5 times to get air out of heater core--it helps if car is up slight slope forward to help air flow uphill to radiator
carefully open screw on top of thermostat housing to let air out of that point -- I hold a shop towel over the screw but it has never spewed out on me, but be safe

You probably don't have a paper gasket between the metal housing and the intake manifold. All you have is a rubber gasket around the thermostat rim. The new one may not even come with a replacement now that I think back. I reused the original--check the box when you get it.

Originally Posted by toastedoats

agreed, whilst in motion, a 180* WILL in fact make a difference, at a standstill, or in hot climates, a 180* on its own will not fully manage lower operating temps

Originally Posted by briancole23

I have one question... am i supposed to open the housing screw while its running or turned off? I did it while it was running and anti freeze did start coming out. I alos did it once while it was turned off and it still came out. It is running at 200 degrees now and I was beginning to think that I am suposed to wait for the system to totally cool down and then do it.