HVAC Pressure Switch UAC For 1973-1974 GMC K25/K2500 Pickup Vehicle Details$23San Bernardino, CA Manufacturer: BMWModel: 2500 This is a Classified ad on eBay for a fixed price of $23, this is NOT AN AUCTION. Click here to see all details. More DetailsPart Type: HVAC Pressure Switch. 1973 GMC K25/K2500 Pickup Engine: 4.1L L6 OHV; FuelSystem: 1BBL; with System Mount Switch;. 1973 GMC K25/K2500 Pickup Engine: 4.8L L6 OHV; FuelSystem: 1BBL; with System Mount Switch;. More Vehicles Like This BMW 2500$24 BMW 2500$45 BMW 2500$60 BMW 2500$300