I never had over heating problem$ til i change thermostate know its over heating.im flusterd

Did you Bleed your Cooling system after you changed the thermostat? There could be air in the system which will cause the engine to over heat. There are many videos on You Tube on how to Bleed your cooling system if you have never done so before.

What made you decide to put in a new thermostat if the truck was running great? Make sure its not upside down..spring side down

and yeah, the cooling system needs to be bled but it's easy, simply top off radiator, turn on heater, run until it gets to normal temp, LET IT COOL don't pop hot cap, then top off,,may have to do it 2, 3x, then put just a little bit of coolant in 'puke tank' when cold, only 1/4 full or less

I agree with both the above answers! Make sure the spring coil is down into the engine and bleed the system... If the problem still persist, you may have a clogged radiator core and it will need a total flush of the system and worse yet to replace the core. Core replacement can cost between $400-$600.00 ! Let's hope its something simple.... Good Luck !!

I live in hot Texas go get the flush kit ,so you can connect a water hose to the heater cor line after installing the tee .That way you can add water while the engine is running. Here's a helpful tip .if your motor starts to get hot......Turn on your Heater the core is a second little radiator.You may sweet but it will add cooling to the water.

It could be over heating due to a blown head gasket.