The 2009 Jeep Commander — the first Jeep vehicle with three rows of seats to carry seven passengers — now features an available 5.7-Liter HEMI® engine capable of 357 horsepower (266 kW) and 389 lb.-ft. (527 N•m) of torque.
Previous engine offerings are still available: The 2009 Jeep Commander’s new 5.7-liter HEMI engine provides better fuel economy, improved idle quality and overall refinement, along with an 8.2 percent increase in horsepower and a 3.7 percent increase in torque compared with the previous generation engine. The HEMI’s new Variable Valve Timing (VVT) improves fuel economy in two ways. First, it reduces the engine’s pumping work by closing the intake valve later. Second, it increases the expansion process of the combustion event. This allows more work to be transferred to the crankshaft instead of being rejected out of the exhaust port as heat. Essentially, VVT improves engine breathing, which improves engine efficiency and power.
The new HEMI® engine also gives drivers its fuel-saving Multi-displacement System (MDS) technology, which seamlessly alternates between smooth, high-fuel-economy four-cylinder mode when less power is needed and V-8 mode when more power is in demand. This optimizes fuel economy when V-8 power is not required, without sacrificing vehicle performance or capability.
The 2009 Jeep Commander’s 3.7-liter engine is a powerful standard single-overhead-cam (SOHC) engine that is efficient, durable and smooth. It produces 210 horsepower (157 kW) @ 5,200 rpm and 235 lb.-ft. (319 N•m) @ 4,000 rpm. A sophisticated Electronic Throttle Control (ETC) system tailors throttle response to pedal movement based on operating conditions and maintains a consistent vehicle speed on rolling grades when cruise control is active. An exhaust gas recirculation (EGR) valve, helps increase fuel economy.
Source: Jeep press