Overhauling Disco front diff: Parts list or references

[mo.eagles]

Last winter one very cold morning ,Thing 2 did not want to move .Thought I had parked it with wet brakes and they had froze. After 15 minutes of warm up it drove to work with no problems the rest of winter . Last week the front diff started clanking and banging especially in rev. I did not take carnuck's advice and drain all of PO's fluids (and water) from diffs. So I'll be doing the same repairs as Dark Side. Good job with the pic's that will help .

[The Dark Side of Will]

The Timken kit from Yukon with a National bearing from CarQuest to hone out to a slip fit on the pinion and use for setup purposes.

[The Dark Side of Will]

I found this page: http://www.4wheelparts.com/hardparts/HP_PartList.aspx?hpDID=51

With this diagram:



To be very helpful in selecting the right slingers or order, as I bent most of mine getting the pinion out and pinion bearings off.

Since DRP hasn't gotten their act together for producing the D30 threaded pinion bearing spacers, I will have to  order a shimmed one.

Does the Eagle D30 have a short pinion or long pinion?

[The Dark Side of Will]

So I've been slow rolling this build and being concerned about other things *WAAAYYYY* too long. I ordered my new garage door 10 days ago with 3 weeks of lead time, so I'm out of other things to pretend I'm busy with.

I'm going to make my own solid pinion spacer, so here are the requirements:

Minimum ID: bare clearance on a 1.375" shaft.
Maximum OD: ~1.670
Minimum length: 2.310 less thickness of outer pinion bearing shims and slingers

EDIT: 1 1/4" sch 40 pipe has pretty much the exact dimensions I need. I snagged a 10" piece of it to use as a bearing press mandrel and then cut up for a bearing spacer. I cut it in a pipe cutter then faced the ends in a lathe.

Relevant dims:
Inner Pinion Bearing Cage ID: 1.772
Inner Pinion Bearing Cone OD small end: 1.670
Outer Pinion Bearing Cage ID: 1.900
Outer Pinion Bearing Cone OD small end: 1.780

Unfortunately I can't find the original crush sleeve from which to measure, which PTFO's me.

McMaster carries rounds shims with 1.250" ID and 1.750" OD (e.g. PN 3088A328 ). The ID of the shims can be smaller than the ID of the spacer because the shaft diameter tapers from 1.375" where the inner bearing cone presses on to 1.125" where the outer bearing cone presses on.

Inner Pinion bearing cone press mandrel:
Min ID: Bare clearance for 1.375" shaft
Max OD: ~1.770 (fit inside inner pinion bearing cage)

Inner pinion bearing cup press mandrel:
Max OD: 2.842
Min OD: 2.660
Shoulder max OD: 2.100
Shoulder min length: 0.780

Outer pinion bearing cup press mandrel:
Max OD: 2.872
Min OD: 2.643
Shoulder max OD: 2.236
Shoulder min length: 0.685

I won't need a press mandrel for the outer pinion bearing cone because once I have the shims for the solid bearing spacer set correctly using the honed out setup bearing, I just install the service bearing with the yoke and pinion nut.

[The Dark Side of Will]

So appaaaaaaaaaaarently, I am an idiot.

The outer bearing seats against the shoulder on the pinion. No crush sleeve or bearing spacer required. I didn't remember there being a crush sleeve that came out, and I thought I had just misplaced it... but there never was one and I just wasn't paying attention when I took it apart. The slinger for the outer bearing is convex up in this photo



Also installed the cups in the housing. It turns out the old races make the best press mandrels. It wasn't clear prior to assembly that none of the cups go far enough into their bores that the old race would also be pressed in and difficult to remove.
The shims were 0.010 + 0.010.
The small baffle has the bulge *TOWARD* the camera in this shot (that's the only way it clears the inner bearing):



The shims are between the baffle and the housing.
Here's the other side of the same shot:

[vangremlin]

Thanks for the pics and good luck wrapping up this project.

[The Dark Side of Will]

You're welcome! Glad to share.

Of course I forgot to bring my inch lbs torque wrench with me to my dad's house, so I won't be able to measure pinion preload this weekend. I'll put it together with a setup bearing and make sure the original shims are reasonable with the new bearings. I'll do the final installation probably next weekend.

After that, I need to reinstall the carrier and verify the pattern, then I can seal it back up and bolt it to the engine!

[The Dark Side of Will]

Honed the setup bearing today.

My dad had a brake cylinder hone, which is definitely the wrong tool for the job. I had him get new stones for it a couple of weeks ago.
I was able just barely to grab the bearing in the drill press vice and use the drill press to turn the brake cylinder hone. I cranked the tension in the hone up as far as it would go. We used a little bit of heating oil from his tank as cutting oil. It became surprisingly cloudy with swarf as we periodically rinsed off the hone in it. We flat wore out a brand new set of brake cylinder hone stones, BUT the setup bearing slips on and off the pinion shaft easily now.

[The Dark Side of Will]

First trial assembly netted 46 inch lbs of pinion preload... The spec is 12-15 with new bearings.  I guess I have to order a shim pack!

ETA: Realized I had installed a protective washer (or maybe just a thick shim) on the wrong side of the bearing. I rectified that error, but I'm still seeing 32 in-lbs!

ETA2: I ordered 3088A937 from McMaster-Carr, which is an assortment of round steel shims with 1 1/8" ID and 1 5/8" OD.

[The Dark Side of Will]

Went 0.007 above stock (0), sanity checked original shim pack (still 32), then .004 (~8), then .003(~11), then .0025 to finally got a reading between the 12.5 and 15 in lb graduations on my torque wrench. Some genius in China laid out the markings on the dial with three marks between 10's... so it doesn't have 12, 14, 16, 18 like an American would expect... it has 12.5, 15, 17.5.  %)

Anyway, pinion bearing preload is set. Next: carrier bearing preload and contact pattern. I sure hope the factory pinion depth setting is right, because fixing it requires removing the inner bearing cup from the housing (and probably mangling the inner bearing outer slinger) in order to reset pinion depth.

[The Dark Side of Will]

Carrier is in place with the original shims, but I did not get the chance to check the pattern today.

[The Dark Side of Will]

The bearing cap bolts are at 45 ftlbs. I found this thread asserting that 45 ftlbs is the FSM number: http://www.jeepsunlimited.com/forums/showthread.php?535132-Dana-30-Bearing-Cap-Torque-Spec

But also found this page saying that it should be 60 ftlbs: http://www.drivetrainshop.com/Dana_30_s/85.htm
My dad has an Eagle FSM... it says 57 ftlbs.

My dad's indicator set disappeared, so we had to borrow one in order to check backlash.
This set came out in spec at 0.010".



We did the first pattern check... which was easy. I tried to take photos of the pattern to post on the internet... which was hard.





Here's Dana's own setup guide:
http://www2.dana.com/pdf/5717.PDF

And a quick read on NAXJA: http://www.naxja.org/forum/showthread.php?t=1064802

It looks like the pattern is a smidge toward the toe but not sure if there's a good enough strip of no contact just below the top land.
However, this is a set of original gears, installed at the original pinion depth in the case in which they were originally installed. The only components I changed are the bearings. It *should* go back together just fine with the original shims, yes? The inner pinion bearing and both carrier bearing shims are original. I changed the pinion outer bearing stack .002 as noted above in order to get the pinion preload right.

What do you guys think of the pattern? Need a better pic?

[The Dark Side of Will]

Hauled the diff up to a friend of my dad's who operates his own shop and has done a lot more drivetrain work than we have. Once we got him over the idea that the drive and coast sides were swapped compared to what he was used to, he liked the pattern and the preload, so we're proceeding to button it up. I swapped out the setup bearing for the "real" bearing, pulled it on with the yoke, then installed the pinion seal... then realized I'd forgotten the slinger, so had to carefully pry the pinion seal back out in order to install it. I used some of the anaerobic goo for sealing Getrag case halves on the OD of the pinion seal to reinstall it, since the factory application had been scraped off by the first installation.

The paper manual spec for the pinion nut is 210 ftlbs. The torque wrench only goes to 200, so that will have to do.
I pulled the bearing cap bolts to 60 ftlbs because the book specifies 57, but one of them felt a little weird. The originals are 7/16-14 x 2.25 with grade *5* markings on the heads. I ordered an ARP 645-2500 kit with five 7/16-14 x 2.5" bolts and washers. The holes are 2.578 deep, so a 2.5" bolt with washer should have almost 0.180 of extra depth left over. That should be plenty. If not, we can run a bottoming tap into each hole.

CarQuest quoted me almost $90 for the remaining three bearings and two seals. We'll see what another local supplier can do this week.

[The Dark Side of Will]

No reason I can't get the diff buttoned up next weekend

So... that was a really dumb thing to say. Of course there's going to be a reason.

The bearing on the left is the one that CQ had... the bearing on the right is the one that came out of the unit:



Oooops. The AMC part number cross-references to a B168 bearing, which is what I had CQ order. The actual bearing is a BH208. I was a and let CQ order the one that crossed from the AMC part number rather than going by the part mark itself... I allowed myself to be victimized by a catalog error. CQ is getting the correct bearing in, but I won't be able to work on it until the 21st.

That bearing is the first part that has to be installed in order to assemble the disconnect mechanism and the right output flange... ok, I'm DIW for the right side.
Cleaned up the left side flange and discovered that it's heavily pitted on the seal journal. Oops sommore. CQ has a 1.375 speedy sleeve on the way, but I still won't be able to work on it until the 21st. At least I can repaint it before then.



Yeah, I'm not being a great project manager with this assembly.

[The Dark Side of Will]

Feh... another week of no progress.
My bearing and speedy sleeve sat around the CQ for a while. The CarQuest proprietor *sent the bearing back* to minimize inventory, even though it was paid for. Sigh. She missed the sleeve, so I have that. A 1.375" speedy sleeve is 27 freaking dollars... Holy cow, they're proud of that thing.


I cleaned up and painted the output flanges, at least. I still need to blast and paint the right flange bearing retainer.

At least the ARP bolts arrived; I installed those without incident. I had to work them in and out a few times to clean the threads, as they're ~0.250 longer than stock.

Output flanges:


I also discovered this:


This is the B168 bearing for 1" diameter shaft and 1.250" diameter bore which we initially ordered but found was wrong for the intermediate shaft to outer housing. it *was* correct in the parts catalog... The diagram just wasn't clear about which bearing was which.

ARP's:


ARP's installed and pulled to 60 ftlbs: