I had the same problem on my 1988 2.9L Bronco II. It seems that there was air in the cooling system somewhere! I paid a fellow in Chattanooga, TN $48 to bleed the system and the problem was resolved. That was three months ago and the fix has stuck. His solution also allowed the heater to generate hot air again, which was a good thing as it gets downright chilly here in eastern Tennessee during the winter. How air gets trapped in the system is beyond me, but there you are. Hope this helps.
i think how you get air bubbles in your radiator is putting the fluid in too fast. if you poor it in slow that should fix the problem if it is just air bubbles.
could be something as easy as retiming your truck
i had this happen to me on a 85 bronco you have to burp the system by raising the front up as high as you can or if you put the flush and fill kit on the heater hose you can put the coolant in there and that solved the problem for me
You have a blown head gasket.
Check the thermostat or the radiator. The thermostat could be sticking or the radiator could be plugged.
Bad thermostat, cap and radiator is a common cause.
Bad radiator, gaskets, water pump, thermostat
You may need to replace the radiator thermostat and gasket.
Fixer pluged radiator or caused thermostat to stick shut.
It could be the radiator is clogged. The thermostat could be bad (prevents the coolant from circulating from radiator to engine block)
Check the fan thermostat.
Check to see if the thermostat got put in backwards. Make absolutely sure it's completely full of coolant.
One reasons a Subaru Forester may overheat is because the radiator may need replaced. Another reason could be the thermostat.
Low coolant, stuck thermostat, failed waterpump, plugged radiator, inoperative radiator fans, etc.
Low coolant, plugged radiator, inoperative fan, stuck thermostat.