Has anyone successfully lowered their straight axle 4x4 truck with the Cummins and how was it done?

I put the majority of my miles on the freeway and instead of trading off for an econobox for better fuel economy as fuel costs keep increasing at staggering amounts and wages stay stagnant, one of the ways to increase fuel economy on our trucks would be to make them more aerodynamic. Our trucks have very fuel efficient engines and have the potential for good fuel economy but the aerodynamics is very poor especially on a 4x4 that sticks way up in the air. Right now, I'm getting 26 mpg but I know it could be increased. Anyways, I was looking at my truck and the possibility of lowering it and it looks like if I lowered the front end, the issue is that the front differential might brush the side of the oil pan. It looks like all that I would have to do is modify the oil pan by recessing the side of the oil pan on the one section. Can that be done? Once I do that, I would be able to lower the front end a good 4-5" so that it comes right down almost to the frame stops. I then could install air bags and raise it when off roads and lower it when on the highway to increase aerodynamics.

 

Even if you lower it, you will have a lot of "dirty" air underneath your truck with the frame, axles, and such.
Do you have a front air dam?
I think I would try that first.

 

well 26 aint bad if you dont use your 4x4 get rid of it and go to a straight axle or gut yours your driving something with the aerodynamics of a garage door its wont do 50MGP like a prius

 

sell your truck.... buy a mazda HAHAHAHA