Rear end decisions...

[metalminded]

btw... i love this...

I don't go to the junk yard... I am the junkyard! Muhahaha

I'm tired of getting questions from my friends like... "why do you have those trucks if they don't run?" or "what do u mean you fell asleep in the junk yard?"

I think i finally found a place on the net i can call home.

 

[metalminded]

ok here we go, i'll get some more pix later

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[LCAM-01XA]

OK, something important you need to know - see where it says to check and a make sure it clears the radius and sits flush, well it won't do that right out the bag. You'll have to chamfer the inner end on one side only so it clears the fillet on the pinion shaft. You'll see what I'm talking about when you slide spacer on pinion. It's not rocket science, just minor work with the Dremel is all it takes. But you cannot skip this, you have to make sure the chamfer is large enough and the sleeve does in fact sit square on the face of that "step" on the pinion shaft. Then you add your shims and go to town.

 

[metalminded]

thanks i would not have picked that up from the instructions... luckily its been 90 here so i just started working on the truck a little while ago. And ford's "ingenious" headlight clips have been keeping me occupied since then!
splicing in a new connector for the back up switch on the transmission, then going to tackle the rear diff. with any luck i'll make it to draining the front diff as well.
you would think that chamfer would have been done at the factory, unless it would be detrimental to another application.

 

[metalminded]

got it apart and cant find my torque wrench, must be in storage. i must have crushed the washer good because the collar alone without any shims is thicker than the washer.

 

[LCAM-01XA]

Remember this is not a dedicated 10.25" Sterling "CSEK" tho, it's for a 9" that we are repurposing. So who knows why they didn't chamfer it, but it's an easy fix either way.

 

[franklin2]

I may have missed it discussed in this thread somewhere, but usually the torque setting for the pre-load on the pinion bearings is set with the rearend apart. The axles and brakes being in place will mess up your readings.

And this shim eliminator does not eliminate the original problem of the splines being loose on the yoke. I don't know if you have tested yours to see how much play is really in the splines, but if there is any, I would still think about torqueing the nut down pretty tight with maybe a little dab of locktite on it to try and get more service out of it if it is worn.

 

[LCAM-01XA]

Is the yoke supposed to be somewhat of an interference fit on the pinion splines? Or is it supposed to slide semi-smooth all the way in till it bottoms out on the bearing?

 

[sle2115]

Is the yoke supposed to be somewhat of an interference fit on the pinion splines? Or is it supposed to slide semi-smooth all the way in till it bottoms out on the bearing?

Mine as well as one's I've replaced fit very snuggly. Not a press fit, but not a slide on easily fit either...I've had to persuade them a little.

 

[LCAM-01XA]

Mine as well as one's I've replaced fit very snuggly. Not a press fit, but not a slide on easily fit either...I've had to persuade them a little.

Kinda how my "new" one was when I regeared. My old one, not so much, loose as all heck. Still she gave me several extra years of service tho. When there is oil slung all over and the pinion seal ain't leaking, nut has backed out and it's time to replace the yoke. Next time it happens, if ever, I'll use the newer style of ring and pinion and yoke.

 

[metalminded]

So when i am checking to see if i have 10inch lbs of preload, i want to be off the ground with the tires off? seems like if the brakes are not adjusted just right or any other number of variables that the reading will be off?
IE, i get what needs to happen in terms of assembly, but how do i get within spec correctly?

 

[metalminded]

i am doing this without the seal in place... seems to be a lot of slop

 

[LCAM-01XA]

Did you remove the differential? You want the axle housing empty while messing with the pinion, only once that you have set the pinion preload properly you install the differential. Therefore as long as the diff (and therefore axle shafts) is out of the housing tires can remain on the ground, since there is nothing to turn them and mess up you readings. In other words:

1) start with axle housing completely empty.
2) install pinion only with spacer and some shims, no seal on the front.
3) slide yoke on pinion and tighten the nut, then check how easy it is to turn the pinion. Your are effectively measuring the drag on the pinion bearings alone, the more preload the more drag and the higher torque value you will see.
4) if the pinion turns too easy that means there is not enough preload, you have to remove the yoke and pull the pinion again and use a shim stack that is somewhat thinner than what you had.
5) if the pinion turns too hard then your preload is too high, again remove yoke and pull pinion and change the shim stack to one that is slightly thicker.
6) reinstall pinion and yoke, torque the nut, and check bearings drag again. If still not right pinion comes out again and you change the shim stack again, then reinstall and take measurements again - you do this till you get to where it takes 10lbs-in to overcome the bearings drag.
7) when you get to that point, remove the yoke again, install front seal, reinstall yoke with RTV on splines, put loctite on the pinion nut, and assemble it for the last time.
8) only after all of this can you reinstall the differential and axle shafts. But again, while working on pinion preload the axle housing must be empty, nothing in there except for pinion and its bearings (and yoke obviously).

Clear as mud?

 

[metalminded]

ok, so there is no way to do this without removing axles and diff? i misunderstood at some point.. i guess this is going to have to wait for more parts and more free time. this is a much bigger project than initially anticipated when i went to fix the leaking seal,and my frustration level/90 degree heat isn't helping.

 

[LCAM-01XA]

Oh, one more thing, what torque wrench are you using - bar or digital or clicker? Bar (or variable digital) is what's needed for the job, you can use the clicker as well but it won't be as accurate. If all you have is the clicker then shoot for somewhat higher torque, as if it takes 10lbs-in to get the pinion to turn the actual bearings drag you'd see with the bar or digital wrench is somewhat lower. Kind of like an electric motor, where the starting current to get it going is higher than what's needed to keep it going once it's going. IIRC the difference was several lbs-in, so if 10 rolling drag is what you're after go for 12 starting on the clicker.

Alternatively you can slide a long wrench thru the yoke (slide the u-bolts back in place for this) and hang a 1lbs socket off its end 10" away from the pinion axis - if the socket alone is not heavy enough to get the pinion to turn, but once you give it a little nudge it's barely heavy enough to keep the pinion turning, you're pretty much right there.