Chrysler's 5.7 L Hemi And Air Suspension
Jeep offers a variety of engines with its Grand Cherokee, including the 3.6-liter “Pentastar” V6 and a 3.0-liter diesel. Our test vehicle came with the 5.7-liter Hemi V8, rated for 360 hp and 390 lb-ft of torque. Chrysler made some changes to the Hemi in 2008 that added variable camshaft timing (in essence, variable valve timing for a push-rod motor). Although it isn't as fancy as the latest direct-injected or dual-overhead cam motors, the Hemi does what Chrysler needs it to.
New to the 2014 Grand Cherokee is an eight-speed automatic transmission sourced from ZF. The extra gears are there to improve fuel economy and acceleration. Although we thoroughly enjoyed the SUV's spirited acceleration, its fuel economy deserves some discussion. There’s a "gas-conscious" Eco mode that alters the shift points and enables cylinder deactivation technology to make your tank last a little longer. Eco mode also lowers the Grand Cherokee at highway speeds (above 55 MPH) on vehicles equipped with the Quadra-lift air suspension, again in the name of fuel economy.
Unfortunately, Eco mode is annoying to drive with. The transmission shifts lazily, and the SUV feels lethargic when it’s engaged. Tossing the shifter into Sport mode livens the experience up, but you pay for it with fuel economy. The EPA rates our sample at 14, 20, and 16 MPG in the city, highway, and combined. We observed an average of about 15 MPG combining city and highway driving with Eco mode on. That dropped to about 13 MPG in Sport mode. Yeah, that's only a 2 MPG difference. Given how few miles per gallon the Grand Cherokee gets, switching from Eco to Sport translates to a 13% loss in fuel economy. This made me cry a little when I filled up the 20-gallon gas tank.
With that said, Jeep's powertrain is enjoyable. The ZF 8HP70 transmission is very refined, which is no surprise since BMW and Range Rover employ the same transmission in some of their vehicles. My wallet doesn't love the fuel consumption, but if you're buying an SUV with a V8, you certainly can't be surprised. Other engine options are available if you want to trade in some of that power.
Quadra-Lift Air Suspension
Jeep equips our Grand Cherokee Overland with an air suspension system dubbed Quadra-Lift. What you'll immediately like about Quadra-Lift is the ability to lower the SUV when you park it for an easy exit, the fact that it automatically hunkers down at highway speeds for better efficiency, and most important, achieving lots of lift for off-roading fun.
You get 4.2 inches of travel from the lowest to the highest setting of Quadra-Lift. The video above illustrates the differences between each height setting, including Parking, Normal, Off-road 1, and Off-road 2.
Since the Grand Cherokee has an air suspension system, it can dynamically alter the SUV's driving characteristics. Selec-Terrain involves a control knob that lets you manually select the optimal setup for snow, sand, mud, or rock. There’s an automatic option that lets the computer decide, also. We left the Grand Cherokee in Auto during our on-road testing, since we didn't encounter any of those conditions.