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Chevrolet Silverado HD High Output Alternators

Heavy-duty Silverado owners hitch up fifth-wheels, goosenecks and equipment trailers, often in cold weather and often before sunrise. Starting a diesel in the cold and then pulling all day asks a lot of the charging system. The products below cover the Chevrolet Silverado HD years you can select in the vehicle finder above. Match your year and engine, then choose a Silverado HD high output alternator for real towing loads.

  • 56 products
  • 1996–2023
  • 170–400 Amp
  • Billet options
All Chevrolet alternators

56 products

Cold Starts and Long Pulls

A diesel works its batteries hard on a cold morning. The starter and cold-start heaters drain them, and the alternator has to put that charge back while the truck idles up to temperature. Then the tow begins: trailer brakes, marker lights, the charge line to the trailer battery and, on heavy trailers, an electric-over-hydraulic brake system. A Silverado HD high output alternator refills the batteries sooner and carries those loads up long grades.

Diesel and Gas Fitment for the Silverado HD

Silverado HD fitment is split by fuel. Diesel trucks from 1996-2000 use one series, and 2001-2007 trucks with the 6.6L diesel use a large case alternator with a side output stud. Gas trucks are listed for 2014-2018 and 2019-2023, again with separate series. Years outside these ranges are not covered here, so match your year and engine before you choose.

Amperage for towing

Options run 170, 240, 250, 320, 370 and 400 Amp. A truck towing a mid-size camper with lights and a brake controller does well at 240 or 250 Amp. A heavy fifth-wheel plus a work light bar and an inverter moves you to 320 or 370 Amp. Trucks that tow, run auxiliary equipment and carry an audio system at the same time belong at 400 Amp. 170 Amp is the lightest step. Size your Silverado HD high output alternator for the heaviest trailer you pull.

Housings and Heavy-Duty Wiring

Choose a billet case, milled from solid aluminum in finishes such as dark blue, natural, black and red, or a standard housing that looks like stock. On a diesel, upgrade the grounds and the charge cable with a Big 3 kit from our wiring kits, and replace tired batteries with a matched pair from our battery selection. GMC owners will find the same fitment on the Sierra HD page. For other Chevrolet models, see our GM and Chevrolet alternators. All of these are Mechman high output alternators built to work as hard as the truck.