My 2000 3500 5.9L usually won't start blowing warm air out the front vents until I get into the low end of the temp guage. This is probably normal however, my rear blower is not sending out any hot air at all. It's sort of just cool air. Any ideas?

Thanks,
Bill

 

Flush the the cooling system, including the heater cores.

 

Had some blankets in the back and they were sitting right next to the vent. Went to take them into the house and there was a very obvious warm spot. Does the rear system only blow warm air when the van is moving? This is maybe what's occurring but is it normal?

Thanks,
Bill

 

The rear should not blow air with out the fan on, but if the vent is blocked then no air will move. The front at times may blow air as the van is in motion and the "OFF" button is not fully pressed in. On mine I can push it far enough in to deactivate the fan but not shut down the fresh air intake.