Has anyone ever done it? I want to change my 3.55 to 4.10s looked on ebay and it would be only about 300.00 just for the Chrysler 9.25 and Dana 44 Ring Gears and Pinions.

What do you think

 

I've done it once and will be doing it on a 14bolt and D60 in the near future. Basically, if you have to ask, you're probably in over your head, gears needs to be set up exact or they will destroy thmselves quickly. You need a few special tools, and in the Chry 8.25 and 9.25 you need a special tool to turn the carrier bearing adjusters as well, not to mention a lot of patience. The front D44 needs to have the carrier bearings pressed on and off to change the shims, you'll likely have to do it several times to get it right setup bearings, same goes for the pinion of both axles.

 

I am in the middle of this right now. It started out as a pinion bearing noise/ leaking seal. With new pinion bearings and seal in hand I dove in. when I got things apart I found the differential carrier cross pin was severely worn down and carrier case (open) was toast. so I ordered a rebuilt trac lok ( the re builder left out the troublesome clips that always break, I wasn't comfortable with that so I ordered new clips and the tool to dissemble/reassemble said trac lok) ordered 4.56's, special notched crosspin and new ring gear bolts as recommended by the FSM. I also had to purchase more bearings for the carrier and axles. ( I also found scoring on my factory axles where they ride the outer bearing, found nice used ones at the pick and pull.) I have purchased for this job also a 0-60 inch pound beam style torque wrench for setting up pinion preload, a tool to adjust the carrier adjuster deals, a tool to hold the yoke so you can tighten the pinion nut, marking compound, shim kit, loc-tite, oils, LSD additive, I still need a dial indicator w/ magnetic base and I think I will be all set.

Now my truck isn't my daily driver, I literally have it just to kind of tinker with. I have really enjoyed researching, learning, and even buying this stuff(completeoffroad.com!!)

That said doing this myself is proving to be a really long and expensive way to rebuild the rearend w/ gears.

MORALE OF THE STORY: unless you want to learn about your truck, collect some tools you may only use once, have it take a bit longer, and always question how accurate your first attempt at setting up a rear end was, leave it to the dealer or experienced shop.

Buying your gears, master rebuild kit, LSD/locker of your choice (new), and getting them installed professionally in my opinion is the best route cost wise and piece of mind wise.

 

I recommend against notched cross-pins, instead the ring gear tooth that's in the way should have the tip ground off. This isn't in the gear pattern and doesn't effect gear strength and allows you to run a full cross-pin instead of a weaker notched one. It also makes assembly and disassembly easier because the carrier doesn't have to come out and the ring gear removed to install/remove the cross-pin. Sounds a little crazy but it's common practice, even Randy's Ring and Pinion does it this way.
This is what my 8.8 4.56 ring gear looked like after I clearanced it for the cross-pin. A dremel with a simple sanding cylinder works well for this.

 

^ i didn't know that. good tip.