Ok so the story is 99 Ranger ext cab (with opening ext cab/doors) 4wd, 3.0, auto trans and about 180,000 it. And it has never had an issue.

Driving to work the other day, starts to looses power run bad with a miss, I then smell antifreeze, temp gauge never moved off the middle. See steam coming out the exhaust when I roll into the parking lot at work.

Further inspection shows head gasket lets go..water in cylinders. BAM locate a exact complete parts truck with a 3.0 with 94000, my wrench buddy swaps in the motor and trans, life is good. Have 8000 on the swappped in motor.

Other day wife drove it to work and said heater air never got hot, temp needle never moved off C. Was fine coming home, had heat and needle in middle.

I drive to work its fine, but driving home needle goes from C to middle, heading towards H, then to middle, to C then to middle again. Had heater hot air, then went cold, then back to heater hot.

I get home smell antifreeze, open hood, it has by passed the rad cap AND the over flow bottle, blew all over the motor. I let it cool ck rad level, add coolant in rad.

Drive it a couple more times and its all good, this am going to work does the crazy needle thing again.

So what you think?

 

my first thought is stuck thermostat.