Search by number: 2009 Chevrolet Impala 3.9L 6 Cyl Alternator ProAmp 11183 $121.00 each OPTIONS: NDenso Unit, 150 Amp ProAmp 11185 $144.00 each OPTIONS: Bosch Unit, 125 Amp, wo/Clutch Pulley ProAmp 11236 $181.00 each OPTIONS: Bosch Unit, 125 Amp, w/Clutch Pulley ProAmpN 11185N $240.00 each OPTIONS: Bosch Unit, 125 Amp, wo/Clutch Pulley 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