This Carquest alternator with manufacturer part number 8489N is a perfect fit for your Chevrolet Silverado 2500 HD Classic 6.6L from 2007. With a voltage of 12V and amperage of 145A, it comes with a pulley included and clockwise rotation. This alternator is a great replacement for your old one and comes with a 1-year manufacturer warranty. The interchange part numbers are 15845337 and 15845338, while the OE/OEM part numbers are AL8520X, 90-01-4449N, 124, 91016, N8489, and 8489AN. This alternator is not a vintage part and has universal fitment. Buy it now and get your vehicle up and running again.