Friday, March 24, 2006

Jeep Commander Engine Options

Jeep Commander buyers can choose between three different engines:

· 3.7L V6
· 4.7L Magnum® V8
· 5.7L HEMI® V8

Those opting for the standard, base level Commander will receive the 3.L V6, but may choose the 4.7L Magnum V8 as an option (with package 28S). The privilege of the larger engine will cost $720.

The HEMI is not offered as an option with the base level Commander. If you want the HEMI, you will have to start with the Limited version of the Commander, which offers goodies such as heated leather seats, improved sound system, etc., and comes standard with the 4.7L Magnum V8. To get the HEMI you must choose package 25H, which will set you back $845 vs. the price of a base Commander Limited.

Let’s talk about performance. The base 3.6L V6 boasts 210-hp at 5,200 RPM and produces 235 lb.-ft. of torque at 4,000 RPM.

The 4.7L Magnum V8 produces 235 horsepower at 4,500 RPM and 305 pounds-feet of torque at 3,600 RPM.

This is only a 12% difference in hp between the 4.7L V8 and the 3.7L V6. However, the significant difference is the torque: 305 lb.-ft. @ 3,600 RPM vs. 235 lb.-ft. @ 4,000 RPM. As any off-roader worth his/her salt knows, this is a significant difference (almost 30% more) and not only that: the peak torque in the V8 is produced at lower RPM. This means that the 4.7L Magnum V8 is a much better option if you plan to do a lot of driving off-pavement, where high torque at low RPM is a desirable.

Now to the HEMI. The 5.7L HEMI V8 produces a whopping 330-hp at 4,500 RPM and 375 lb.-ft. of torque at 4,000 RPM. That is a lot of torque for the off-road enthusiast, and a much welcome hp rating to motivate the Commander on the road, considering that it weights 6,200+ lbs.

Fuel economy is not the Commander’s forte, with highway mileage for the 2wd models rated at 21mpg for the V6, 20mpg for the 4.7L V8, and 19mpg for the HEMI. For those opting for the HEMI, there is the small consolation that in light acceleration or cruising speed its Multi-Displacement System (MDS) deactivates 4 of the 8 cylinders to achieve up to 20% fuel economy (which theoretically would improve highway mileage on a 2wd vehicle to around 23mpg).

Just a few simple tips can help owners of Chrysler Group engines with Multi-Displacement System (MDS) get the most fuel mileage possible from their 5.7L HEMI® V8 engine.

  • Keeping speeds to 65 mph or below – MDS uses four cylinder mode most at these speeds
  • Use cruise control – this helps maintain a steady speed, generally allowing the HEMI to run on four cylinders for longer periods
  • Accelerate more gradually – the HEMI will provide V8 power whenever it is requested by the driver
  • Use a steady throttle whenever possible – this maximizes four cylinder mode

Tags: , , , , ,