Help with Pinion Nut / Preload Issue
 

Reaching out for some thoughts on this. I have previously regeared my axles. At that time, all was good. This summer I replaced the factory rear DS with a 1350 adams. In the process, I had to remove the factory pinion flange in order to install the new 1350 yoke. I’m sure everyone who responds to this is generally familiar with what most the DS manufactures will tell you when doing this, just use some red Loctite and snug that pinion nut back up to ~160 ft lbs and make sure there is no play. Well, I could never achieve that. I put the new yoke on, and using 2’ torque wrench and over 250ft lbs force, couldn’t get the nut any tighter and still had a smidge of in/out play. So, I rolled with it and threw some salt over my shoulder. Well, trip to Moab this summer brought about rubi e-locker issues (kept getting stuck locked). I have a friend that gave me his old rear rubi axle with his locker. The plan was to swap my ring gear to his locker, install and reshim as necessary, figuring it buys some more time at least. Well, long story short, in this process it became glaringly obvious that the pinion is loose. I’ve tried impact drivers rated up to 1190 ft lbs, figuring with that breakaway spec I have to be seeing maybe half that torque for tightening. I’ve removed the yoke and started from scratch twice. I just CANNOT get it any tighter than before, and that small bit of slop remains. I’m at a loss at the moment.

I know swapping in a new yoke isn’t rocket science, and something that is done by someone every day I’m sure. How can I be the only one having an issue like this? I’ve searched around a good bit, and find a lot of threads about pinion bearing preload and whatnot, but don’t see anyone in my situation really. Working on garage floor doesn’t enable getting much leverage with a big cheater pipe, so I’m wondering if my next move should just be pull the axle entirely to get better access to the pinion nut with some manual leverage, but then I start thinking damn…..how much force should I have to put on this just to get to the point even starting to hit some pinion preload. I mean, I’m not having to crush a new sleeve or anything.

Anyone have an idea? Doesn't this amount of force seem excessive? I’ve reached out to Adams as well but have not heard back yet.

So you are not replacing the crush sleeve?

Well, realistically this was a simple swap of flange for yoke this summer, at which point no, was simply swapping as all videos and instructions show. Never could get that tight again though....there was just a bit of play in the pinion with the new yoke.. This original problem is kinda secondary to swapping the carrier, but generally I'm balls deep in a big mess. LOL. I'm starting to think this isn't a torque problem, but that something is prohibiting it from tightening any more. I'm going to remove the pinion tonight. I have thought that I might just need a new crush sleeve, which would be a pain as I don't have a good way to pull the bearing.

Theoretically my pinion would have been perfectly fine, i'd swap in new carrier, reshim carrier appropriately (hoping all was still fine with the current pinion shim), and roll on. Sadly, not the case.

I have 2nd axle sitting to the side. Might try to install this same yoke on that tonight and see what it's like. At the time of my regear couple years back, all was well. I don't recall any play when I removed the factory flange this summer. How could my pinion have worked loose enough to have about 1/8" play forward/backward?

Did you put the washer back on before the pinion nut? Otherwise it shounds like you need a new crush sleeve.

Yes, reused the same washer with a little RTV on it to seal. Y, I fear you might be right about the crush sleeve. Gonna inspect things more tonight. Thanks for the response.

Agreed. Sounds like the crush sleeve. There are companies that make crush sleeve eliminator kits. Takes a little more time to set up the first time, but then you never have to worry about it again.

y, thx. I've looked at the eliminator kits. They seem like a better long-term idea, but definitely take some setting up. Just got home and about to go brave dang chilly temps to fiddle with it more.

Well, pinion is removed and I think I've found the culprit, which is indeed the crush sleeve. It was lodged about 1/8" up on the shaft, which coincidentally was about the play I thought I felt. It took a surprising bit of force to dislodge that free. I'm going to guess that while tapping on the yoke before, I drove the pinion down, which caused the sleeve to get lodged higher. then when trying to put the nut back on, it wasn't enough to to dislodge the sleeve, leaving that much room in the set up. UGHhhhh. -

https://cimg6.ibsrv.net/gimg/www.jk-...5647b2a615.jpg

So, I have a new crush sleeve, and I have new pinion nuts, but my issue now is I have a slightly jacked up thread on the pinion. The first one. It was like that when I installed the yoke, so that must have somehow happened at regear a couple years back -

https://cimg4.ibsrv.net/gimg/www.jk-...f1a38909e2.jpg

https://cimg5.ibsrv.net/gimg/www.jk-...e2b660fb9e.jpg

I don't have a dremel or thread files. Any good thought on how to address that? Little hesitant to take an angle grinder with a cut off to my pinion threads. Worth buying a dremel to help carefully address or does someone have a better suggestion?

I've done it with much larger nuts and bolts but if you can make a die out of the old pinion nut then you'd be in good shape. The tough part is getting the holes drilled nicely. We hard a large press. On the flip side, I've made a tap out of a bolt and a small angle grinder. If you've got a small enough tip then maybe you could get inside the nut and grind out some channels.

I sat and patiently worked at those threads will small triangular files to get it best I could.

I'm a gluten for punishment and aggravation, so I reinstalled that pinon with the current crush sleeve one more time. Results is no play in the pinion as I had before, BUT, the pinion seems to turn too easily compared to what I know is a good axle/pinion sitting to the side in the garage. Seems like still not enough pinion preload IMO, but can't get that nut any tighter. I have serious doubts about having success crushing a new sleeve, but might attempt that tonight. :sigh: