Thanks for the input everyone. I was able to solve the problem today by replacing the t-stat yet again I did a coolant flush because it looked like someone had mixed green with orange at some point and It was a black color. The biggest problem I had was the coolant system had some air in it. I have been adding to the radiator all day while parked on a incline. I didn't think the system took so long to burp all the air out but after doing this the truck is back to normal.

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1998 4cyl 4wd 5 speed.