Join Date: Aug 1999
Location: Kaysville UT USA
Feedback Score: 0 reviews
The Vacuum pump controls the damper door. But the default is to full Defrost. So if the vacuum pump or line is bad, You should be getting all your air blown up the defrost.
The Vacuum also controls the Auto Hubs. Turn your ESOF switch to 4x4 and see if your front wheels lock in. If you are spinning on the back and the fronts are not turning, then you have a bad pump or line.
A new pump is fairly inexpensive. I think the last one I swapped out was $100 and it's just 2-3 bolts. A 15 minute repair.
15 F350 CC Lariat SRW LWB Ruby Red, Ultra Predator Wheels with Toyo 295/65R20, BAKflip Fibermax tonneau, Diesel Products LED lights in the rear bumper and 20" light bar in the front bumper, Firestone Airbags and Airllift Wireless compressor.
11 F350 CC Lariat SRW LWB Tuxedo Black Sold at 145,000 milesl