Over Heating issues '94 Pickup 4x4 Manual V6 3.0L

I am having Over Heating issues with my '94 Toyota Pickup 4x4 Manual V63.0L when driving on the freeway for 1.5+ hrs at 80mph with the A/C on. I havea brand new water pump and thermostat. I had issues previously before I installeda new thermostat WITHOUT using the A/C. After installing the new thermostat I havenot had any issues when NOT using the A/C. I can drive in the city all day withthe A/C blasting and not have an issue. I am assuming it is because of thespeed I go BUT if I even go 70mph I still have the same issue. Regardless thetruck shouldn’t get that hot when if I’m not “red lining” it. I live in AZ soits obviously hot as hell and using an A/C is nice. I have never let the truckget to the “red” in the temp, I will either pull over or throw the heat on fullblast before it gets there. Also, when I 4x4 I never had an issue with the tempeven before the new thermostat. I don't have any leaks "that I know of" and the radiator looks fine and I don't see and damage to anything. I am going to buy a K&N cold air intake to see if that helps but I shouldn't have to. Lastly the truck has 191,000+ miles on it.
Thank you!

 

As long as the truck never gets into the red, I think you're ok.

 

K&N intake won't help

 

Have you flushed the radiator? Sounds like some of the tubes are plugged. When running the A/C, the extra heat from the A/C radiator is preventing the coolant radiator from doing its job.

 

Check for coolant in the oil and oil in the coolant.
That generation 3.0 had a recall for head gaskets.

 

Maybe the fins are full of junk. I would check that if you haven't.

 

Yes I have flushed the coolant. Should the fan in front of the engine able to be moved by hand when the truck is not running? A friend said the clutch could be bad if I can freely move the fan. "The fan should not be able to be moved by hand"... Weather it is in gear or neutral I can freely move the fan with VERY little restriction. I have a manual if that makes any difference. In case you were wondering I am not talking about the clutch that you push in to change gears that is brand new as well.

 

fan should have resistance.start truck take a piece of paper put on front side of radiator see if fan pulls paper against radiator,No pull paper No pull air.