1982 GMC S15 with A/C;. 1983 GMC S15 Submodel: Base; with A/C;. 1983 GMC S15 Submodel: High Sierra; with A/C;. Part Type: HVAC Heater Core. 1983 GMC S15 Submodel: Sierra Classic; with A/C;. 1984 GMC S15 Engine: 1.9L L4 GAS SOHC; EngineVIN: A; FuelSystem: CARB; 2BBL; with A/C;.