Compressor: 62-81 era AC GM NEWBrand new compressor for the older 62 81 GM vehicle. This newly engineered compressor series features improved internal design for greater efficiency with R134 refrigerant and offers a significantly lighter build.. For optimal installation, after filling the new A C compressor with oil, position it so the front seal faces downward for 1 to 3 minutes. This allows the seal to become properly lubricated, reducing the risk of refrigerant leaks during