Mechman high output alternators · Authorized dealer

Chevrolet Astro High Output Alternators

Plenty of Astro vans still earn a living. Contractors, techs and couriers run inverters, shelf lighting and battery chargers off the 4.3L, often while parked at idle. Every Chevrolet Astro high output alternator on this page is a Mechman unit listed for 1987-2005 vans. Use the filters for amperage, finish and housing, then confirm your year with the vehicle finder at the top of the page.

  • 49 products
  • 1987–2005
  • 170–400 Amp
  • Billet options
All Chevrolet alternators

49 products

Running a Mobile Shop off the 4.3L

A work van spends a lot of its day idling with the loads on. A tool battery charging station, an inverter, LED cargo lighting and a strobe package can all pull at once. A factory-size alternator falls behind at idle, and that is how a van ends up needing a jump at the end of a job. An Astro high output alternator raises the charging current so the batteries stay topped up between stops.

Two Fitment Groups

The 4.3L comes in two groups. Vans from 1987 to 1995 use one alternator family, and vans from 1996 to 2005 use another. Match your year first.

Sizing Output for Your Upfit

Mechman high output alternators for the Astro are listed at 170, 240, 250, 320, 370 and 400 Amp. Choose an Astro high output alternator for the loads you run every day.

  • 170 Amp: a light upfit with LED lighting and a laptop charger.
  • 240 or 250 Amp: a mid-size inverter for tool batteries, plus lighting.
  • 320 or 370 Amp: a larger inverter, a second battery and warning lights running together.
  • 400 Amp: a full mobile service setup with heavy inverter use.

For most work vans, a standard cast housing is the practical choice. Billet housings, machined from solid aluminum, add finish options like Machined, Natural and Black. An isolated second battery from our AGM batteries helps keep tool loads away from the battery you start with. Upgrade the charge wire with a kit from our wiring kits, and see our harnesses and regulators if the factory plug is brittle. GMC Safari owners have a separate page, and the wider GM alternator collection covers other Chevrolet vans and trucks.