So last winter replaced cracked radiator every thing good all winter. Over the summer trans got stuck in 4th gear replaced with a remanufactured trans. Un related but truck sat for 3 months till I found and got money and had time to swap. Got it done 500 miles the front seal from the water pump blew and poured out all my antifreeze so replaced the pump and all the lines and thermostat. Could not get heat after that so I'm adding 1 gall of antifreeze a week driving only about 100 miles cant find the leak then pass side batterie covered wit antifreeze noticed the resivior was crappy and looked cracked so replaced that now leaking from drivers side but cant find where. It got hot but not over heated I pop hood so see fluid level and where the radiator tank mats to the aluminum was leaking at the seam so replaced the radiator again. So new everything under 400 miles. I can start the truck let it run for 15 mins and barely off cold drive it for 30 min to work it get to the middle of the gauge but no heat unless I get on it and I have heat for like 5 min then cold air.i can be driving for 2 hr no heat un less I get one it. After a week of doing the rad. I added like 1gal of fluid thing just working the air bubble out but still nothing. If I let it get hot the resivior tank all most emptys and I went to open it while running to add and so much pressure in the tank and the fluid goes to the full line and I put the cap on and it sucks back down get in the truck heat for like 5 min then cold again. So lost.