Drivetrain Cross-pin trouble on rebuilt 8.8

Rdub6

So while I wait to figure out my rear end issues
5 Year Member
Dec 29, 2017
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Long Island, NY
I’ve recently rebuilt my rear end, and am installing new Moser 5lug axles. First try, the cross pin is hitting the ends of the axles.
F1E826D6-EFD6-48CA-9D36-34340A1C97D9.jpeg

I am within spec on my clutch packs, and actually already have the smallest shim I had in there, .030.
I decided to measure the axle ends, after the c-clips.
Old:
345EBC81-1B88-4F63-801A-BBDA8765C613.jpeg


New:
67659915-ABFE-4C06-8C8F-BC4919DED3BD.jpeg

It is this difference that is causing the trouble.
Should I shave the c-clips, or shave the end of the axle? Or is there another solution.
Thanks for the help guys!
 
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Are you grabbing the axle ends and pulling outwards as far as you can before trying to insert the pin?
Yes. Even tried a pry bar on the button end to push them out more. They are definitely bottoming out. The only difference between these and original (besides the additional lug) is that button end measurement.
And just for the hell of it, I put the four lug axles back, and everything slides together like butter!!
 
I can also get one axle in (either side) and the cross pin will go in with a little persuasion, but there is zero end play.
I emailed Moser to see what they suggest at this point. They are supposed to be “direct replacement” for use with rear disc and NRC brackets, with sn95 flange!
 
I’d see what they say. Hopefully something good as I was going to use those same axles!
Yeah, I’m stumped right now. I even took the carrier apart again and double checked those measurements. The clutch packs are within spec, with a .030 shim. I don’t even have a thinner shim if I wanted to loosen things up that way. That was the thinnest in the pack (and I really don’t want to loosen the pressure on the clutches).
I’m confident it’s back together right, especially since the originals fit right in. The button ends look slightly warn on those, but I guess that’s to be expected after 30+ years.
I can’t imagine a machine shop charging too much to take 5-7 thousandths off each one? That’s probably the route I’ll go, unless I hear different.
Not in a rush, but these roadblocks are frustrating!!
 
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I'd machine the axle tip down before I thinned out c clips. How much between the groove and the tapered edge on the new axle ? It shouldn't be that costly to get them trimmed down.
 
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After a lot of thinking, and a few nights sleep on it, I decided to take it apart one more time and measure my clutch packs. I remember them being on the high side of the spec, but that was with the thinnest shim I had. I started measuring the individual steel plates. The new were 6-7 thou thicker than the old. I took two old that were still in good shape (dull, no glaze) and replaced one new on each side.
Cross pin slid right in, with just a few taps at the end. There is very little end play in the axles, but I’m thinking it will loosen up once the new clutches wear in. For now, I’m calling it good!
 
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i had the same problem with mine as i just rebuilt my 8.8 with the new carbon clutch pack, seals, and bearings. my pin wasn't going in and i was getting frustrated so i gave it a whack with a 2.5 lb dead blow. not hard just almost the weight of the hammer and it slid right in. the ends have a chamfer so it shouldn't be a problem.