Does anyone know how to change a thermostat in a 98 Jeep Grand Cherokee?

I have heat when it is in park and running but as soon as I drive a few miles, no heat. Mechanic friend said try changing the thermostat as the radiator is intact with no leaks. Want to do it myself. Anyone ever done this before?Does anyone know how to change a thermostat in a 98 Jeep Grand Cherokee?Is this the V8 or the 4.0?

I have changed the complete cooling system in my Wrangler and did it in about 4 hours. The thermostat is a simple job. Make sure the engine is cool and you will have to drain the collant about half way. If you want to do it right just drain all of the coolant and replace it with 1 gallon of new coolant and the rest water. Your thermostat is usually held in by no more than 2-3 bolts. Make certain to remove all of the old gasket material before installing the new thermostat and gasket or you will have more trouble. Go to your local auto parts store and purchase a Chilton manual or something comperable for your car. It is an easy afternoon job even for a nubieDoes anyone know how to change a thermostat in a 98 Jeep Grand Cherokee?I have-easy!Does anyone know how to change a thermostat in a 98 Jeep Grand Cherokee?It's easy, buy the thermostat, then follow the big top radiator hose down to the engine, where the hose connects in the housing that holds the thermosat, there should be 2 bolts holding it on, remove the bolts and pry the cover off, you will need a new thermostat gasket as well. Replace the thermostat, gaske and cover, bolt it back up and your done. Check your collant level, you will probaly loose some coolant changing the thermostat.