No front heat-?

[BigRoryG]

So I put in new thermostat and my front heat still doesn't work. The rear heat seems to work fine and gets hot in a reasonable amount of time.

The fans all work properly but will only blow hot on rare occasions and usually only after I've been driving for more than 2 hours.

Thoughts?

[BigRoryG]

that's a 95 Suburban 2500K 4WD, by the way.

[redbird2]

Have you check the hose coming and going from the heater core, one hot other should be some what cooler not cold, could be plugged core, how is the are flow good or so/so if it so/so i would try blowing out the core acroos the fins to get dirt out of them.