It depends on the speed and the amount of revs you use, if you drove around all day on loose ground in low or high box 4wd you can you can tootle around and hardly use any fuel.
When in 4wd you are not usually travelling at any great speed so you wont be revving as high to move the car save the occasional blip on the gas to get over an obstacle or muddy patch.
If you are in 2wd with your hubs locked at normal driving speeds you will use a tad more fuel, not because you are driving the front wheels as you should not be in 4wd you will be in 2wd but you will have created a little more drag on the front do to the drive shafts being locked to the front wheels, though no drive from the engine is going to them.
Getting a percentage comparison between 4wd H/L and 2wd usage would be nearly imposable due to the many many variations involved.
Last edited by
Drift on Thu Jun 04, 2009 7:28 pm, edited 1 time in total.
Reason: Add , should not