I have a 2000 F150 4.2l v6. The temp guage never gets off the cold line and there is no heat in the truck? Any thoughts? I have already replaced the t-stat without fixing the problem. It is a 5 speed manual. What else should I look for?

 

Okay so I disconnected the top radiator hose from the radiator after it had been sitting for about 5 hours and turned it on to see if the t-stat was working. About 2-3 second later coolant poured out. Does this mean the t-stat is stuck open? What else could be wrong? I know the truck was ice cold when I started it so no coolant should have come out of the hose.

 

in my experience, 99 times out of 100, what you describe is a failed thermostat.

I'd try (another) new one.

 

It's on my to-do-list for tomorrow. Will let you know how it turns out. Thanks for the input. I guess I will go to NAPA and get a good one. Would you recommend a 195, 205?? What temp t-stat would be best?

 

Several years ago that was a debated issue.
For me, I used the factory thermostat.
I think it is 195. (?)

 

About a year ago, I replaced three thermostats on my Aerostar before I got a good one. These were allegedly quality units and I avoided the cheap ones. On my van it's somewhat of a PITA. I will also recommend getting one from a dealer.
FWIW, I now have good heat.

 

I went and bought a Stant 192 degree and changed it out. Everything is working properly now. Turn out is was the t-stat. Thanks guys.