Part Type: HVAC Heater Core. Aluminum Heater Core. Heater Core. 2007 Chevrolet Silverado 1500 Classic Submodel: Crew Cab Pickup; Engine: 4.3L V6; RPO Code D07; w/ Custom Front Floor Console;. 2007 Chevrolet Silverado 1500 Classic Submodel: Crew Cab Pickup; Engine: 4.8L V8; RPO Code D07; w/ Custom Front Floor Console;.