2004 jeep grand cherokee overheating. changed water pump, thermostat. no heat from heater. and still overheats

The fan relay is the most common failure point on these
Car overheats Chrysler Vehicles Ricks Free Auto Repair Advice

Check you water pump to see it it is leaking. Check your coolant level.

thats a good possibility, though most thermostats get stuck open, not closed. check the coolant level to make sure its ok, a lot of times the water pump will go bad, and allow air to seep in causing air pockets, thus making the vehicle overheat, also is it blowing good heat?? might be heater core leaking.

sounds like one of two problems your fan is not working properly or you radiator is particularly restricted

check the thermostat or your radiator might be stopped up

Bad themostat, dirty radiator (the front of it), corroded interior core of the radiator, weakening water pump, bad radiator fan.....just to name a few. More than likely? Low antifreeze level, or the thermostat.

If you put the thermostat in correctly (spring towards the engine) that should be OK. Likely if the water pump wasn't leaking or had a bad bearing, you wasted your $ on that.
If you re-filled it and did not have the heater on high heat, you may have some trapped air in there. But, still overheating says another thing. If you have a blown head gasket, it can pump compression into the cooling system and drive the coolant from the core. It will also overheat. You can have that tested at most any decent shop that will do a hydrocarbon test to find that.I think someone makes a chemical test kit for that but not sure if it's very expensive or not. White smoke from tailpipe will also be an indicator as will be any coolant in the engine oil or coolant on one or more spark plugs. If it turns out that it has a head gasket problem don't stop looking for problems as often a faulty fan or obstructed radiator can cause the initial overheat that caused the gasket to fail.

Yes...and no. and you left out the electric fan, and clutch on primary fan. You need to determine the cause by testing. Unless the water pump is leaking or the bearing on the shaft is loose or noisy, it is not causing overheat. Primary cause of overheats is coolant loss. check everything for any and all leaks. Next, change thermostat. It's cheap and easy to replace plus it becomes unreliable after any overheat. Check electric fan to make sure it comes on when needed, and last, check that radiator is not either externally blocked (leaves etc) or internally blocked with calcium deposits. If you have any white smoke from tailpipe , coolant in engine oil or on spark plugs, you have a blown head gasket.
Hopefully it's something simple!

Change your Thermostat.