Search by number: 2004 Ford F-150 Heritage 5.4L 8 Cyl Alternator ProAmp 8318 $150.00 each OPTIONS: Naturally Aspirated; 110 Amps ProAmp 8251 $159.00 each OPTIONS: Supercharged; 130 Amps; Custom High Amp not Available ProAmpN 8318N $151.00 each OPTIONS: Naturally Aspirated; 110 Amps ProAmpN 8251N $190.00 each OPTIONS: Supercharged; 130 Amps; Custom High Amp not Available 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