I'm getting ready to replace my vacuum pump for the second time. The first replacement was an $85 knockoff and didn't last 2 months. I'm thinking that I might have a leak somewhere. I have the lines going to the auto hubs plugged (Warn hubs now). what else besides the heater controls run off of this pump? It's been pretty unseasonably warm around here, but it's only a matter of time before all hell breaks loose. And it SUCKS when you can't get heat down to your frozen toes.

 

Just the hubs and HVAC. Check for leaks and dont buy China knockoff.

 

I just picked up one of these for vac testing a chainsaw.
Mityvac Vacuum Pump - Save on Mityvac Pumps at Harbor Freight!
Sears had the best price but the link is from HF.

Would work to see if you have any leaks. You could block off the line to the hubs for testing purposes. I have Warn manual hubs so I blocked my vac line to the hubs permanently.