1990 was the first year of the Geo Tracker. 1999 was the first year of the Chevrolet Tracker. So the answer to your question is 1999.
195/75/R15
The thermostat on a 1999 Chevy is in the lower radiator hoe unbolt it at the water pump.
Look at the bottom or rear of radiator
Should be at the bottom or rear of the radiator
Depends on where you go.
behind the glove box
Disconnect the lower coolant hose.
Yes. '99-'01 same
Pull the engine.
When you have the heater on, does it just blow any air at all? or no air?
90 INCH LBS. Again: INCH LBS.