Okay let me throw this one up see if anybody can figure out what I'm doing wrong here.
I have a 2005 Dakota 4.7L V8 (rebuilt motor) 4x4 crew cab with 3:55 gears on the 9.25 axel. I had originally installed my 2-inch leveling kit up front and put on 265/75/16's with Rancho's all around. 3 days after install I took my first long trip with my truck to the eastern Sierras for my annual fishing trip, total of about 750 miles round trip. On that trip I averaged about 24miles per gallon. This was all hand calculation based off my gas fill up receipts. I was very happy with those results. After that trip we planned our 2nd trip back out there 3months later. With only the 2-inch leveling kit up front my truck was slightly higher up front than the rear. My leveling kit also came with 1 inch rear blocks and pinion angle correcting shims. So I installed that before the next trip being that on the first trip the rear end sagged quite a bit with all of our gear in the back of the truck. We left on our trip 4 days after I installed 1 inch rear block and pinion angle correcting shims. So now on this second trip my truck has the 2in leveling front & 1 inch rear blocks with pinion angle correcting shims. Only this time my fuel mileage was extremely poor compared to the last trip at only about 14mpg! The only thing I noticed that I'm thinking about now is that it was hard to put the axle PIN back into the leaf pack I had to use a ratchet strap to pull the left side of the axle back far enough to realign the PIN into the Leaf spring pack. This was my first time ever installing rear blocks truck. Maybe I did something wrong? Should I have had that much trouble aligning the axle back with the leaf pack? Anyone with experience installing these please feel free to chime in any info will help thank you.