First off I want to introduce myself. my name is Josh and I live in PA. I recently picked up a 2003 quad cab hemi. I believe it has the 3:73 gears in it. Its lifted 3 inches with 35x12.5 nito mud graplers sitting on 20 inch rims. Im getting 8.4 mpg. I want to increase that alil. Thinking of a throttle body spacer and cool air intake. I dont think those alone will raise it too much or I could be wrong. I have been told that the 4:10 gears would give me a good increase. Heres my problem. I dont know anything about gearing or buying them, or even what to look for to buy and where to buy it. Any help/input I would greatly appreciate. Thanks guys.

 

If it's a 1500 it would have 3.55's or 3.92's from the factory, and w/ those tires you probably want to go to 4.56's. Check out moesperformance.com or airram.com as they sell the gears and master install kit that you will need. You may want to just find a local 4 wheel drive shop and get the parts from them and have them do the work. That way if something goes wrong and it can, they won't have any excuses. The most important thing is to find a good shop that has plenty of experience doing ring and pinion installs w/ the chrysler 9.25 rear. Post in the 3rd gen section if you need more help or do a search for more info.