Part Type: HVAC Heater Core. 2007 Chevrolet Silverado 3500 Classic Submodel: Crew Cab Pickup; Engine: 6.0L V8; Except RPO Code D07; w/o Custom Front Floor Console;. 2007 Chevrolet Silverado 3500 Classic Submodel: Crew Cab Pickup; Engine: 6.6L V8; Except RPO Code D07; w/o Custom Front Floor Console;.