6-speed automatic heavy-duty transmission

Electronically controlled, equipped with:

  • Overdrive
  • Internal transmission oil cooler
  • Tow/Haul mode

Requires Vortec 4.8L V8 SFI FlexFuel engine, Vortec 6.0L V8 SFI FlexFuel engine, gaseous 6.0L V8 SFI engine or Duramax 6.6L Turbo Diesel engine.