The Silverado 3500 comes standard with a 353 hp 6.0-liter V-8. A 365 hp 6.6-liter turbo-diesel is optional. Both engines are mated to a six-speed automatic transmission. An 8-foot cargo box and dual rear wheels are available on 3500 models. It is offered in regular, extended and crew cab configurations, with two cargo box lengths. The 3500 is available in three trim levels: WT, LT and LTZ.The Chevrolet Silverado is fully redesigned in 2007.