04 Rubicon 42RLE to AX-15 transmission swap

Got the rear set of gears installed and adjusted, this has been a fun project. I spent more time than probably necessary, being everything is new I decided to start at zero so I could dial everything in perfect. After leaving all pinion shims out and taking initial measurements I realized I needed .058” pinion shim, guess what I took out, yup, you guessed it, .058” which brought my pinion depth to the exact dimension engraved in the end. I used a home brewed measuring system consisting of magnetic base with indicator , I stuck the base to the pinion nose then swept the bottom of the bearing scallop then found that dimension on my surface plate with gauge blocks. Once I had that dimension I could do the rest of the math to find my pinion depth. After getting that right I started with the original set of carrier shims which were too tight, I shimmed the carrier away from the pinion .015” which created almost .015” of backlash, a few more adjustments and I had the backlash at .006” (.006-.009 spec) and 18 in pounds on pinion pre load (14-19 spec)

Two things noteworthy for anyone thinking of tackling this job, be sure to oil your bearings when checking pinion pre load, mine was reading almost 30, after oiling it was at 18. Second, when driving in carrier shims, sandwich super thin shims in between two thicker ones and put the thinner outer shim towards the bearing race, it’s smoother and corners have radiuses on them making it easier to get the thinner ones to slide in.

Overall fun project but definitely not for the novice LOL

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Nice work! Whereabouts in Michigan are you? I'd like to regear, I have the right tools and the knowledge to do so...but there is nothing like having another set of eyes to look at your work.
 
Mike_H said:
Nice work! Whereabouts in Michigan are you? I'd like to regear, I have the right tools and the knowledge to do so...but there is nothing like having another set of eyes to look at your work.
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From the “thumb” wish I was closer, I would come watch someone else flop around on a creeper lol
 
tigman250 said:
From the “thumb” wish I was closer, I would come watch someone else flop around on a creeper lol
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Ha! I wish you were closer too. When I do my re-gear, I think I'm pulling the axles to work on them on the bench. Been flopping around on a creeper for two days doing my tummy tuck, and that is enough!
 
Mike_H said:
Ha! I wish you were closer too. When I do my re-gear, I think I'm pulling the axles to work on them on the bench. Been flopping around on a creeper for two days doing my tummy tuck, and that is enough!
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Did my tummy tuck last year, I have to space these big jobs apart enough so I forget about how much I hate rolling around on a creeper 😂
 
Gear swap is complete, I had a strange growl when letting off the gas at higher speeds, this caused me to completely disassemble the rear thinking there was something not happy. After checking all the tolerances while taking apart I did add .002” more preload to the carrier because I could get .001 deflection when prying the carrier side to side thinking that was my noise. Good news is the gears were set up properly from the start, bad news is my transfer case is guilty of the noise.

I will say on road it does indeed behave much better, shift points feel right now and they even feel more firm, not sure if that’s placebo or not, more drive time will tell. Excited to get it on the trail now......but first, I have to rebuild the transfer case lol!!

Anyone have a good source for a complete bearing, seal and chain kit?
 
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