Search by number: 2004 Ford F-150 Heritage 5.4L 8 Cyl Alternator ProAmp 8318 $143.00 each OPTIONS: Naturally Aspirated; 110 Amps ProAmp 8251 $151.00 each OPTIONS: Supercharged; 130 Amps; Custom High Amp not Available ProAmpN 8251N $188.00 each OPTIONS: Supercharged; 130 Amps; Custom High Amp not Available ProAmpN 8318N $188.00 each OPTIONS: Naturally Aspirated; 110 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