Jetsr6 Not only was there no mpg increase but that single drive axle thought I owned a tire shop as well I was going threw a set of super single tires ever 50,000 miles which in turn was 6600 dollars a year just for drive tires as well as the traction was no where close to that of 6X4 that's why I have RS-23160 Locker axle sitting in my shop on the floor. I run the northwest and 79,000 lbs plus all the time the single drive didn't have any trouble handling the weight it just didn't work in my operation. The only advantage I seen with a 6X2 is the weight loss I loss 538 lbs with that setup.
2006 Detroit series 60 515 hp 1650 torque
now if your pulling lite loads on flat land more than I was it would probably work fine. But I would never do it again to many cons and not enough pros for me. If you look at eatons website even there they say up to 2% gain in mpg with 6X2 setup but 2% of 7 mpg is only .14 mpg increase it would take a long time paying for it even if you didn't have excessive tire wear like I did
There's a shop in IN that will do a front lift axle conversion for $6500, worst case scenario. Meaning if everything went wrong, it would only cost $6500. Hopefully if everything went smoothly, it would be a bit less.
A guy I work with has a front lift axle. He loves it. But he also said that his drive tires do wear faster. About a year on a the 4.