As others have pointed out, backflush the core and check the plenum. Vehicle HVAC systems are susceptible to debris building up and causing blockages. Pinholes in the heater core can also be causing problems as they allow coolant to seep out without the telltale sign of a large puddle while allowing air into the system.

 

I can hear the motor going when I turn it on so what else could it be

 

The motor will turn but the coupling to the baffle may be junk. Reach up in where the motor went and see if you can manually move the baffle. Might be time for Heatertreater.com

 

+1 for heatertreater.com

 

R u talking about the blender door?

 

Yup. There is a coupler between the little motor, and the axle that the door is mounted to. That little feller likes to crack, so you don't get full travel on the door, so neither the heat, nor the a/c work as well as they should.

 

Baffle, blend door. Aach! They both start with "B."

 

The AC blows real good and cold just not the heater but I'll check that out next

 

I've seen in a video where they were troubleshooting a heater not blow in and they said if u move the temp dial from hot to cold fast enough u can hear the blender door slapping the wall. Would that be the same case in the truck?

 

Only if it was cable actuated... The motor will go the same slow speed regardless