How do you replace the thermostat located on a 2000 Pontiac Montana?

Answer 1

I just did it tonight. on my 2000 MT, remove the air cleaner tube, throttle body, the thermostat is just below the throttle body in the aluminum cast housing. two bolts to remove, one was easy the other was a real $%&^!!. It is behind the exhaust cross over tube. Good luck. Took me about 2 hours. TIP - use WD-40 on the air cleaner tubing to get it to go back on the Throttle body. Another persons comments.

From the beginning of automotive design way before the Model T, items that need frequent service must be easily reached for replacement. The position of the Montana and Venture thermostat just violates every rule in design. If you could remove the screws to the casting over the thermostat, on my van there is not enough room to remove the part. This is not the only part like this under the hood of the van. Try the hoses to the heater core tubes.

Most all manuals say "remove the exaust crossover" which is made impossible by a heat shield that has bolts in the back that can not be seen or easily accessed. Oh, there is also a metal water pipe to the heater across the area that keeps the heat shield over the crossover from coming up if you could get it loose. The metal pipe has some brackets and you have to bend it to get out of the way once it is detached from hoses. If the shield comes up then you can access the three stud bolts that attach the crossover to the front manifold. Then there is the intake to the throttle body that probably needs to be removed to get good access. The thermostat also sits facing out where gravity wants to let it drop out while you try to put the casting back on the intake. It goes on and on. I see why this is a 4 hour job for the GM service folks, just for a thermostat!

I have yet to figure out how to replace the thermostat short of cutting out the front section of the heat shield over the crossover pipe.