Heater only gets warmish. Thermostat stuck open?

[GWeakland620]

That sounds a lot like my issues. I was thinking I had left something off and had a gap. I will have to look into that.

 

[MTBLAZER89]

What's the thermostats temp? Should be 195*, but people insist on using lower ones, so not a given. If you have a 195* stat and temp is truly below that by a significant amount, the thermostat is bad.

This is a recent development. T-stat hasn't been changed since I've owned it.

Replaced the thermostat with a new 195* and back flushed the core.

Seems to be working normal now My coolant was also super green!! I think I may have topped it off before I went on deployment last year and also just had way too much coolant. Added a little water after I swapped everything. Coolant is good to -10 and engine runs at 200ish. Nice hot air coming from the vents.