Search by number: 2011 GMC Sierra 2500 HD 6.0L 8 Cyl Alternator ProAmp 11234 $138.00 each OPTIONS: 2 Pin; Bosch type unit; 125 Amps ProAmp 8550 $149.00 each OPTIONS: Standard; 145 Amps ProAmp 8301 $154.00 each OPTIONS: 2 Pin; Optional 160 Amps ProAmpN 8301N $182.00 each OPTIONS: 2 Pin; Optional 160 Amps ProAmpN 11234N $275.00 each OPTIONS: 2 Pin; Bosch type unit; 125 Amps Why is there more than one unit for my car? Look at the TECH SPECS when more than one unit is shown for your car. AMPS (ELECTRIC CAPACITY): must match you vehicle electric requirements. *** Call us if you are looking to increase your unit capacity! OE ALTERNATOR MANUFACTURER: It is recommended to match the Make of your alternator