Just changed the thermostat and still no heat in the car. antifreeze is full

Your thermostat is stuck, or your antifreeze is low, or your inline heater core valve is stuck closed. Has to be one of those three. Check the antifreeze first. If full, check the heater core valve. then the thermostat.

you still have air trapped in the cooling system. Get front of car as high up as you can on a hill. Cold engine - loosen radiator cap, fill with 50/50 antifreeze mix. Start engine and run until upper radiator hose is hot (thermostat open). Engine should burp air and maybe spill some coolant, that's ok. Once burped, tighten cap, shut off engine and let it cool down while keeping the reservoir full. It will **** coolant out of reservoir as it cools. Keep it full.

If still cold air, take to a shop that has evac/fill equipment; they will **** air out and repalce with coolant. About $80.

gerry

check your radiator resivior, make sure that there is antifreeze up to the full when hot line, if your low on fluid the first thing you lose is heat.

Was it knocking in the radiator when it over heated if so you most likely got an air lock in the system by pouring the new antifreeze in to fast. You need to add it real slow and once you think the radiator is full start the truck and let it warm up and leave the radiator cap off until the thermostat opens and then add more antifreeze because when the stat opens the level will go lower. Once you are sure the antifreeze is circulating an full then you can go drive the truck. Some people use a 50 percent mix of antifreeze to water but I always use 100 percent antifreeze it runs cooler.

Remove rad cap start vehicle be sure engine antifreeze is full.After running for 5-10 minutes you should see air bubbles rising nonce they stop close cap you should have heat.If you do not perhaps you might consider removing the thermostat to make sure the spring side of thermostat is facing the engine and not the thermostat housing.

New thermostat may be faulty. May be stuck open. Remove rad cap and with rad full and eng cold - start vehicle. The coolant should not circulate until eng reaches design temp of thermostat. Let me know if this helps you.

Sounds as if your new thermostat is set at a lower operating temp. Assuming your Cooling system is full of Antifreeze and no airpockets present.

low radiator coolant level OR bad thermostat and Lord I hope not,a leaky heater core.Check fluid level first the look at thermostat replacement only after the level check. Good luck and bless you in advance if you should catch a cold...from the cold!

You have to remember that refilling antifreeze you must know what to do, must make sure that all Air pockets are removed from the raditator.

That is common since the a/c condenser is in front of the radiator. It may just be time for you to service the cooling system. If you have the orange antifreeze in your system, there only good for 5 years or 150,000 miles and then it needs to be flushed out and replaced with new antifreeze. Make sure the new antifreeze has a 50/50 mix (antifreeze/water) to much antifreeze will gel up when heated causing poor heat transfer and to much water will boil over. Water has great heat transfer but boils at 100C' so antifreeze is added. Service the cooling system for now, don't worry about the thermostat till you change the antifreeze unless you want to replace it too.  Good luck and keep me posted.