I have no clue what the science is on changing the rear gearing. I know I can DIY it if I get the parts. Has anyone done a write-up for gear swap. Im wanting to change my 3.55 to at least a 4.10. What kind of benefits are there with the change.

 

there's a writeup in the 3rd gen ram section, I just had a shop swap my open for an LSD but didn't change the gears. they had to set bearing preload to exact amounts and measure the backlash before removing to refer to when installing. I'm not sure how much of that you will need to do since you are just swapping gears. if you have the 9.25 rearend (octagonal cover) there is a screw to adjust for preload. I'm not sure how the 8inch is, but some use shims.

As far as benefits, you will have more torque throughout the gears and higher RPMs in your top gear. so basically you will have noticeable get-up-and-go and easier towing feel, but lower fuel mileage at freeway speeds

 

As stated above, pinion depth and backlash muse be set correctly to ensure long-lasting gears. A year or so ago, I had my 9.25" open 3.55:1 swapped to LSD 4.10:1. I am VERY happy with the results. City fuel mileage improved, towing mileage improved, highway mileage with no trailer dropped by 1.5 or 2 mpg. For me this is a Win-Win since I don't usually take trips in the Dak unless I'm towing a trailer. I had a knowledgable shop swap the gears for about $300 because I was getting ready for a 2500 mile trip.

 

I am not sure on price etc.. but I will share my experience with 4:56's front and rear. I bought the truck them but think 4:10's would be more ideal for stock applications (stock tire sizes etc.). With 4:56;s my city mileage improved as did towing but running down the highway at 70 really takes a few notches off the mileage. IMHO 4:10's would be perfect.

 

I went with the 4.10 from 3.55, excellent move, great all around city driving, and it sure runs nice on the highway, I paid 1600.00 for my 4x4 back in 05, parts are cheap, but the labor is where they get you, for all the money you will spend on, exhaust, tuners and intakes, save the money and get the gears, you will love them.Have a shop do it, so much easier, plus you get a warrenty, DIY, if you do the set up incorrectly and shatter everything, your responcible