I recently bought a '03 Supercrew. When I crank the truck up with the a/c on it sounds like it's blowing extremely hard and loud from the windsheild vent. After a minute or so you can hear the air changing from the top to the dash vents. Is this normal,if not what should I be looking for ?

 

Reports are a vacuum issue exists with the vac line going down to the vac reservoir located under battery. It deteriorates and leaks, the system goes to defrost with inadequate vacuum to the function door actuator.

 

Thanks Bill ! I'll check this on Monday.