FailEx can't seem to get its act together and get me the parts I ordered 2 weeks ago, so I'm not getting much done on the axle. I did, however, put the old pinion in last night to get a pinion depth measurement. I learned something when I did. I had trouble getting the pinion nut tight enough to achieve the right bearing preload. I pulled on my torque wrench until it clicked at 150 ft-lbs. Preload is supposed to be 10-15 in-lbs, but I was only at 9.5. No problem. I grabbed my impact gun, rated at 600 ft-lbs and laid on it. That got me up to... 9.5 in-lbs. Okay, I am using a tiny pancake compressor, and the gun is old now, so I grabbed my buddy's DeWalt battery gun, rated at 700 ft-lbs and went to town. That got me all the way to... 9.5 in-lbs. Once the pinion nut bottomed on the crush sleeve, it wouldn't go any further. I don't have anything more than 700 ft-lbs, so I'm done. Really, only big-rig shops with five-figure compressors, big hoses and 3/4" guns can go higher.
It's not easy to crush a crush sleeve. The average crush torque on the average axle is 300-400 ft-lbs. On my 1-ton axle, it takes more than I'm able to produce.
All that to say, when I was under my truck, cursing myself for not marking the pinion nut before removing it, there was an easy fix. I could have simply brapped the nut back on to as much as my impact gun could muster, and driven happy. It wouldn't have mattered. Once the nut bottoms on the crush sleeve, it doesn't move any further without really long cheater bars.
That feeling when you realize your $2,500 axle build wasn't necessary...
Don't get me wrong, my axle needed attention. It had started to howl a bit, that bearing was sad, the brakes were a mess, etc. That said, it was still running and could have kept running for some time still.
For the next guy, just know that failing to mark your pinion nut probably isn't a big deal. Put it back on and tighten it up. You'll feel it bottom out on the crush sleeve, and it won't go any further after that. As for me, I'm off to buy some really long cheater bars for the new crush sleeve.