320 Amp High Output Alternator - 2001-2007 6.6L Duramax LB7/LLY/LBZ & 1996-2004 GM Gas - Black Billet

320 Amp High Output Alternator for 2001-2007 6.6L Duramax LB7/LLY/LBZ

Fits the 6.6L Duramax in 2001-2007 Chevrolet and GMC HD trucks (LB7, LLY and LBZ) and the 1996-2004 GM gas trucks that share the same case and mount. This is a direct bolt-in upgrade over the factory unit — same mount, same pulley position, no bracket modification.

Diesel engines spend most of their working life at low RPM, and that is exactly where a stock alternator runs out of headroom. This unit holds 200+ amps at engine idle and delivers a full 320+ amps at cruising speed, hot rated — enough for a lift pump, auxiliary lighting, a winch, a plow, a welder or a competition-grade stereo without watching your voltage sag at every stoplight.

Engine codes covered: LB7, LLY, LBZ

Vehicles: Silverado Sierra 2500HD 3500HD, Suburban, Tahoe, Escalade

Manufacturer specifications and full fitment

Installation Notes:

This unit comes equipped with a smaller 1.75 inch diameter alternator pulley, and will require a slightly shorter drive belt for proper belt tension.  Not recommended for sustained use above 5,000 RPM engine speed.

The Elite series 320 amp HOT RATED alternator offers 200+ amp output at idle RPM, and excellent durability. 6 phase technology, combined with massive twin rectifier assemblies and 12 diodes makes these alternators totally durable for daily use, while still maintaining great output at low RPM. This alternator, (like most high output alternators) will come with a slightly smaller pulley on it and will require a slightly shorter belt to be installed for proper belt tension. Shorter belts are available and any local auto parts store.

Fitment Guide: