4-speed automatic transmission

The Hydra-Matic^® electronically controlled 4-speed automatic transmission with overdrive is engineered to provide smooth, seamless shifts for Silverado^® models equipped with either the Vortec^® 4.3L V6 or the Vortec 4.8L V8 engine. This transmission includes a Tow/Haul mode that adjusts the transmission shift pattern to reduce shift cycling, providing increased performance, vehicle control and transmission cooling when towing a heavy trailer or hauling a heavy load.

On Crew Cab™ models, requires Vortec 4.8L V8 SFI FlexFuel engine. Not available on Extended Cab Long Box models.