Follow the upper radiator hose down to the engine. It attaches to the thermostat housing. Two bolts hold the housing on. There may be accessories, brackets, etc, that may have to be removed because they will be in the way. Remove the housing, lift out the old thermostat, remembering which way it came out, and replace with a new one. Newer vehicles now use seals instead of gaskets. Use no sealer when putting the housing back on.
Drain the water from your 1997 GMC Yukon cooling system. Remove the water supply hose. Remove the thermostat housing retaining bolts. Remove the old thermostat and replace with the new thermostat.
When you service the cooling system.
Replace the Thermostat >10 dollars
remove the 2 bolts that hold the thermostat housing to the intake manifold which the upper radiator hose attaches to the housing then just pull the thermostat out and replace.
Its on the front top of engine,follow the top outlet hose from the radiator to to the engine block,where that ends at block,there will be a thermostat neck housing,the thermostat is under that neck housing generally it has two bolts on it,its a pretty easy job on these vans...
you have to replace the whole assembly
wiring diagram for GMC 2500?
Follow the upper rad hose from the rad back to the engine. The part the Hose connects to on the engine is the thermostat housing. Remove it and the thermostat will be in there.
It is located at the engine end of the upper rad hose. When replacing it make sure the spring goes toward the enigne.