mpm17 wrote:
Just some thought going thru my head. But, it stands to reason if you lift a jeep and put bigger tires on it the fuel mileage drops significantly. Now with that in mind would it stand to reason there might be some increases with a lowered liberty and maintaining some original equipment sized tires? But lets go a step further than this.
-Convert to two wheel drive(less mechanical drag and less weight if you remove the front diff and related pieces.
-Lowered to reduce the frontal area(less aerodynamic drag)
-Lower numerically rear gear ratio(lower rpms at interstate speed) Factory 4.10 to a 3.55 or 3.21 is available
-Engine tune and a downpipe for more torque at lower engine speeds to go with the rear gear
I know it would be easier to buy a car to get better fuel mileage. I like to be different and experiment so initially just a rear gear change and disconnect the front drive shaft. This would be nothing more than a daily driver. I have a lifted Liberty already and its not a practical daily driver.
This would all be done on my second Liberty. Helpful input is appreciated and negative comments are not. Keep those to yourself. Thanks.
The two best things you can do for your Liberty CRD to increase fuel economy are...
1) Get an engine tune and matching transmission tune that are geared for economy. Green Diesel Engineering had excellent tunes until the EPA clipped their wings. I understand that Yeti tunes are very good as well.
2) Get your engine operating temperatures up higher. North American Liberty CRD vehicles are subject to politically influenced pollution control regulation that forced Daimler Chrysler to make changes to the R428 engine that are detrimental to the reliability, power production and fuel economy of the engine. One example of this is engine operating temperatures. The rest of the world gets these engines with 195 degree thermostat valves in them; we here in North America get 176 degree thermostat valves to lower NOx emission levels. The NOx levels are lower here, but at the expense of an engine that does not combust the diesel fuel efficiently. This also contributes to the engine being clogged out with pollutants because it never runs hot enough to burn some of them off.