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Your pinion bearing at the pinion head (inner) is a pressed on fit. ie: shop press. The bearing at the yoke (outer) is a snug fit and will jam pretty easy if it's not perfectly aligned. but you should be able to slightly tap it side to side and have it fit down all the way to the shoulder, where the shims go that determine pinion bearing pre-load. If it doesn't slide on then something is wrong. Can you measure the internal diameter of the bearing and the outer diameter of the pinion shaft? there should only be a .002 difference or so.

My final assembly was oil slinger and .012 shim. That is between the inner bearing and the pinion head.
The oil baffle goes between the inner bearing race and the housing.
 

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Discussion Starter #442 (Edited)
If it doesn't slide on then something is wrong. Can you measure the internal diameter of the bearing and the outer diameter of the pinion shaft? there should only be a .002 difference or so.
Thanks Doc. I'll have to measure it when the new one comes in. I just couldn't imagine trying to get it on without a press and then trying to get it off every time I go to set the preload for each pattern run.


I finally got into the garage tonight to get the axle ready for the 1st pattern run, and just didn't have enough time tonight to get that far. I got the initial RGS and NRGS bearing shim stacks figured out and got the preload on the pinion set after the 9th time.

Inner pinion shims = .047" (Slinger = .030", Baffle = .015", Depth marking Difference between pinions = .002")

Outer pinion took 9 total times to get it into spec.(20-40in lbs rotational torque for new bearings, 10-20 for used)

1st attempt: .085" = unregisterable preload
2nd attempt: .075" = unregisterable preload
3rd attempt: .070" = unregisterable preload
4th attempt: .060" = unregisterable preload
5ht attempt: .055" = unregisterable preload
6th attempt: .050" = 15in lbs rotational torque
7th attempt: .047" = 18in lbs rotational torque
8th attempt: .043" = 45-50in lbs rotational torque
9th attempt: .045" = 28-30in lbs rotational torque

Pinion nut torque spec used = 210 ft lbs (spec is 200-220)

Total carrier shim stacks = .080"

Here are my starting numbers for 1st pattern:

inner pinion shims = .047"
outer pinion shims = .045"
RGSB = .060"
NRGSB = .020"

Hopefully I can squeeze a couple of hours tomorrow night to get the backlash set and the 1st pattern run... ?
 

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Discussion Starter #443 (Edited)
So I have a question to anyone with experience in setting up a shimmed D30.

Say I have to change the depth of the pinion after running a pattern and say I need to increase the depth of the pinion.

1) will I need to subtract from the outer pinion shim stack while adding to the inner pinion shim stack?
2) Hypothetically, would I need to move shims from the inner stack and add to the outer stack to decrease the pinion depth? (hypothetical because I can't run without the baffle nor slinger)

I ask because I think I would need to do so in both scenarios so as to keep in the ballpark with preload of the pinion bearings, right? or do I have this conceptually wrong?
 

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Yes, whatever you add to the pinion shim to increase depth, will need subtracted from the outer stack. And vice versa. If you decrease pinion depth, you need to add to the outer stack.
You are doing great, keep up the good work.
 

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Discussion Starter #445 (Edited)
So I spent most of the afternoon fighting with the backlash on the D30.

After about 15 or so attempts, I finally had suitable numbers to run the 1st pattern.

Fun Tip: be sure to get quality measuring calipers or use a mechanical micrometer. The number of times I had to remeasure the shims in different places on the shim was in the forties to sixties. After settling on the correct sizes of shims, I came to realize the least amount of shims = the better. These harbor freight digital calipers were okay, but the variations in the shims added with the occasional inaccuracy(.0005") led to excess iterations on each shim measurement.

I found that the gear oil getting into the stacks, as well as the smallest amounts of crud, made the process all that much slower. Using the least number shims in each stack equates to fewer headaches trying to figure out why the same sized stack required a dead blow hammer with the case spreader. It should have snugly dropped in every time. I found myself needing to tap it in late in the process and prying it out a couple of times because of oil and crud getting in between the shims over the course of changing the stacks several times.

*Use the thickest shims possible to make your stacks. The number of shims in each stack should be as few as possible to make your calculations, and it will make the process easier.

I finally settled on the first run of:

Run 'A'

Inner Pinion Shim = .047"
Outer PInion Shim = .045"
NRGS Bearing Shim = .036"
RGS Bearing Shim = .045"
Backlash = .005" - .006"
Drive Pattern = High Heel Side
227082


Coast Pattern = Slightly High Centered
227083



My pinion depth is too shallow and needs to be deeper, and I think that I might need to slightly decrease backlash? It seems to be inbetween a depth and backlash problem according to the usual FSM diagrams.

I'm hoping to get one more pattern in before bed later tonight, but I did want to get this up there in case someone with experience could echo my thoughts or correct what I am doing wrong.

Any help is appreciated! Thanks!
 

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Discussion Starter #446 (Edited)
Run 'B' :

Inner Pinion Shim = .057"
Outer PInion Shim = .057"
NRGS Bearing Shim = .035"
RGS Bearing Shim = .046"
Backlash = .0045" - .007"
Drive Pattern = Slight High, Heel Side

227084


Coast Pattern = Slight High, Slight Heel

227085




It's still not deep enough. The backlash this time was odd. I had a larger disparity, but only in a small section of the ring gear. Also, the outer pinion shims also needed to increase when lengthening the pinion into the housing. It seemed a bit counter-intuitive. I need to think on that one a bit.

I'm starting to get a good feel/touch for correct pinion preload rotational torque, and backlash. Many, many times in and out with the carrier and many, many times setting the pinion depth...

ugh, time for bed.

Thoughts on any of this? Thanks!
 

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I'm proud of your efforts. It's not an easy job, and very very time consuming. We understand why paying to have your gears done is so expensive.
The only gear oil I had in mine was a very light coat on the bearings. I know it's hard to keep it off the shims cause they are right beside it. Make sure you have a load on the gears when checking your pattern. It sounds like your are working solo, so having someone hold the brake while you rotate that pinion is out of the question. You can tie a shop rag around the pinion, use a zip tie to keep it real tight and use a wrench on the ring gear bolts to rotate the carrier. It's a pain, but the pattern has to be under load. You can be a little higher on the back lash. I think you are right at the minimum.
Sorry I never thought about the total number of shims, but yes, use as few as possible to eliminate contaminates from between them. Sorry if I didn't mention using a micrometer and not a caliper to measure shim thickness. If you have high quality tools such as Starrett you can be sure of their accuracy, but harbor freight tools, while ok have higher tolerances for accuracy. Especially on the thinner shims. I used my caliper with a very light touch to get a quick measurement, then used the micrometer (.0001 to 1" is plenty big enough). They usually come with a calibration rod which is 1" exactly so you can check it's accuracy.
Every time I changed shims I had clean towels on the bench and I would rub both sides over the towel then place on another clean towel. I used a fine point sharpie to write the sizes on them. After it dried I used gear oil to wipe it off. I was left with a very faint image of the numbers. I felt the ink could throw off my measurements.
You are doing great work. This is where the patience is mandatory, but the rewards are astronomical!
 

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Discussion Starter #448 (Edited)
I'm proud of your efforts. It's not an easy job, and very very time consuming. We understand why paying to have your gears done is so expensive.
Thanks! and yeah... me thinks next time I'd seriously consider having the work done for me. My back isn't getting any younger

The only gear oil I had in mine was a very light coat on the bearings. I know it's hard to keep it off the shims cause they are right beside it. Make sure you have a load on the gears when checking your pattern.
I used a bit too much gear oil in my attempt to get more yield on the mustard packs, so I'm thinking I'll try to add a bit more load next time than I already am. I've been using an 1/2" drill to rotate the gears and a chunk of wood to get the needed drag on the ring gear to get the pattern.

The thinness of the compound and the lighting made taking better pictures difficult. The pattern is discernable in person.

I am gonna make a run tomorrow and grab some Prussian Blue at the local napa.

It sounds like your are working solo, so having someone hold the brake while you rotate that pinion is out of the question. You can tie a shop rag around the pinion, use a zip tie to keep it real tight and use a wrench on the ring gear bolts to rotate the carrier. It's a pain, but the pattern has to be under load.
Yup, just me. Unfortunately, my 70 yr old mother couldn't help in the garage. Besides, the axle is on some jack stands. I'll be looking into a bigger shop towel. Thanks for the zip tie tip.

You can be a little higher on the back lash. I think you are right at the minimum.
Yeah, it's acting a bit strange. I have had High spots show up on the gear in dissimmilar spots depending on the current setup. Moving .001 from one side to the other is pushing this ('B') pattern all around specs (.005-.008) but never in between the numbers. I didn't think it was that much of a deal because I'm thinking I'll have at least another three or four iterations before I get it fine tuned close to finished.

Sorry I never thought about the total number of shims, but yes, use as few as possible to eliminate contaminates from between them. Sorry if I didn't mention using a micrometer and not a caliper to measure shim thickness.
No need to be sorry, for I was just sharing my experience as I am going through this. I know JandDGreens is about to embark on this fun filled patience testing journey, and I thought someone else could benefit from my pain. ?

Besides, it gives everyone a few minutes looking and thinking about something else other than apocalyptic end times scenarios for a few minutes at least.

If you have high quality tools such as Starrett you can be sure of their accuracy, but harbor freight tools, while ok have higher tolerances for accuracy. Especially on the thinner shims. I used my caliper with a very light touch to get a quick measurement, then used the micrometer (.0001 to 1" is plenty big enough). They usually come with a calibration rod which is 1" exactly so you can check it's accuracy.
As I don't really regret not purchasing better equipment, I do regret not borrowing better equipment from my mechanic brother. He has a couple of high-end mechanical micrometers. Doh! ?‍♂

Every time I changed shims I had clean towels on the bench and I would rub both sides over the towel then place on another clean towel. I used a fine point sharpie to write the sizes on them. After it dried I used gear oil to wipe it off. I was left with a very faint image of the numbers. I felt the ink could throw off my measurements.
I completely agree, and will fully clean them every time I am about to run a pattern. As well as for the final bearing install.

You are doing great work. This is where patience is mandatory, but the rewards are astronomical!
I am really looking forward to the first several, non-break in period, stomps on the gas pedal. I am getting tingly just thinking about it.... or is it the coronavirus working its way into my brain?!?

Hey thanks Doc, I really appreciate the helping hand as always brother. Your immediate family are in my thoughts during this messed-up situation we're all living through. I keep hearing people say that it's such an exciting time to be alive! I'm starting to think they're just high... :LOL:

Thanks Gluck!
 

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Thanks, I'm not gonna individually reply, sorry kinda lazy today. But you got the jyst of it. I forgot you are on stands. If you have a large breeze clamp that might help also. You're doing good. I like the distraction your very detailed and technical post give me. I have some major personal issues that are slowly getting better, but this is a welcome reprieve. Thank you. God bless you.
 

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Discussion Starter #450 (Edited)
Run 'C' :

Inner Pinion Shim = .076"
Outer PInion Shim = .068"
Pinion Preload = ~23-25 in lbs
NRGS Bearing Shim = .047"
RGS Bearing Shim = .039"
Backlash = .006-.009 (slightly out of spec)

Drive Pattern = Close to Centered, but slightly Toe

227088



Coast Pattern = Slightly High, Too much Heel

227089
 

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Discussion Starter #451 (Edited)
I think it is good enough to call it the farthest depth-wise for the pinion. Pinion depth has been bracketed. It is time to start moving it back out slightly. I am betting it will be approximately .002-.004 back in the opposite direction.

I am hoping that the depth correction clears up the coast heel issue on its own. I am slightly confused as to how it could possibly be corrected on the coast side without messing up the drive side of the teeth. I am hoping it is a backlash thing.

I find it interesting that I have to increase shim thickness in the outer as well as the inner to find proper pinion preload whilst moving the pinion deeper into the housing. It would appear conceptually that the mechanics of the pinion preload is more of an increasing the distance between the two pinion bearings rather than the distance between the two pinion bearings being the same and having to move the pinion in relation to the outer pinion cup. I still am unsure to exactly why this is the case. Food for thought...
 

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Drive side pattern on c looks good. .003 out of round on the ring? Did you flat file the ring gear and carrier to make sure there are no burrs? You didn't put an excessive amount of lock tight on the bolts?
25 in lb preload? I thought it was in the teens? It should be what ever you put in the inner bearing, take the same amount out of the outer and vice versa. I don't have my pattern samples handy. But I think a little to the heel on the coast side is ok with a good drive pattern. Sometimes you can't get them both centered.
 

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Discussion Starter #453 (Edited)
Drive side pattern on c looks good. .003 out of round on the ring? Did you flat file the ring gear and carrier to make sure there are no burrs?
I did not file the ring nor the carrier. I paid special attention to that possibility the night I cooked a ring gear in the oven. It is possible I missed one, but I am thinking it is a different factor that is causing it: Mostly inadequate measuring equipment.

I am working with issues in the shims stacks on the carrier. I've been having an issue with getting .001 moving from one side to the other. It's mostly the measurement issues. However, I am finding that I do not have the carrier preload in the stacks either. I've been a little sloppy and impatient with the backlash and those stacks in Runs 'A' and 'C'. As I have been going along, sometimes getting impatient, sore, and needing a break: I find that I have been thinking in my head that I have a few more patterns to run.

So the slacker thought process in my head reads like this:
If I keep the sloppiness of the carrier stacks close (+/- .002-.003), I will be moving the range/ballpark in the correct direction until I get close to perfect and then I will tighten up and perfect it. I've found that initial measurements of the carrier stacks on the 'A' pattern run; were inaccurate. Therefore, my measurements going into 'C', and 'B' runs are dissimilar from the start of 'A'.

Going into this next run 'D', I have resolved to re-check the total carrier movement, and readjust my current numbers. Mostly, this is an issue with backlash and carrier preload. Now that I have gotten close with the pinion depth: I really need to be accurate with these numbers.

So gonna be fixing the slop in the shim stacks and carrier preload. As for the possible burrs on the ring: if I have to tear it apart, clean them, file down and reassemble: I will. I remember checking both the ring and the carrier and did not see or feel anything. It is entirely possible I missed one, but I don't think so. We shall see.

You didn't put an excessive amount of lock tight on the bolts? 25 in lb preload? I thought it was in the teens?
No excess Loctite on the ring bolts. Just a small stripe on two sides of each bolt, and not a large amount either.

The 1997 XJ FSM calls for 15-35 in lbs for new bearings:

227090


This was the issue with varying information on the web I was alluding to about a page or two back in this thread. Some have them in the lower range like you stated, and some have more than what the FSM calls for. It depends on which company's 'helpful tips' guide you look at. Even the Billavista page has differing information than the FSM. So I just decided to stay with FSM specs on everything,

It should be what ever you put in the inner bearing, take the same amount out of the outer and vice versa. I don't have my pattern samples handy. But I think a little to the heel on the coast side is ok with a good drive pattern. Sometimes you can't get them both centered.
I have been thinking about this. My rebuild kit came with shims for the inner race cup, and not for the pinion head. It is possible that is what is going on here and I need to get different shims. I am uncertain. I need to think more on this. It could affect slinger depth and the outer bearing getting starved. I have to look more into this.

I have been looking around the interwebs and looking at some gear pattern charts. The pinion depth and backlash are causing the disparity in the pattern. I may not fully get the pattern perfect on the coast side. It could be a poorly ground ring and gear set or perhaps there is a burr I have missed. I will cross that bridge when I get there.

I did get an ultra-solid backlash on Run 'B'. So I am leaning more towards the carrier shim stacks, and preload problems causing my abnormal backlash issues.



I appreciate the interest and mental flossing my friend. Sleep well... I'm off to clean up the slop and get the next pattern done before retiring for the night... (y)
 

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Discussion Starter #454 (Edited)

Mostly good information, but I think he fudges up something at the end of the video. However, I am not an expert. Sure as hell not an intermediate.... yet.
 

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The video does a nice jib explaining the overall process. But I agree, when he didn't know why some patterns didn't stay centered, makes me wonder.
Go by what the fsm says. I think I made mine around 12-15.
 

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Discussion Starter #456
Go by what the fsm says. I think I made mine around 12-15.
...and you're fine right? So, there's a little bit of wiggle room here, and I am hoping that whatever I end up with is just fine and at worst I have to rebuild it in 220,000 and not 275,000 miles. I am praying that I do a good of enough, solid job so that at least I don't have a vibration.

Again, I appreciate the flossing bud.

Back to it.
 

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I've wheeled 33's for 2 years on mine. And still going! #Thumbsup.
 

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Discussion Starter #458
Run 'D' :

Inner Pinion Shim = .073"
Outer PInion Shim = .065"
Pinion Preload = ~20-23 in lbs
NRGS Bearing Shim = .040"
RGS Bearing Shim = .046"
Backlash = .0045-.007

Drive Pattern = Centered, Slightly Toe

227091


Coast pattern = Slightly High, I/B/W Center and Heel

227092
 

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Discussion Starter #459
Going into this next run 'D', I have resolved to re-check the total carrier movement, and readjust my current numbers. Mostly, this is an issue with backlash and carrier preload. Now that I have gotten close with the pinion depth: I really need to be accurate with these numbers.
Total carrier movement was very close: a difference of about .0005". I've found that the majority of my issues with the shim stacks are me just having to recheck the stacks as I reassemble. The .002"s and .005"s are plentiful and finding the correct oddball .001" or .004" takes an annoying amount of time. Initially, when I labelled all of the shims, I measured them in an inconsistent way, and having to relabel as I am pulling them from the carrier to the bench is taking a bunch of time as well. So mostly the equipment AND the users' inaccuracies are costing extra time. In short, use a quality micrometer and take the time to label them correctly the 1st time.

I highly recommend taking an hour or two dinner/lunch break in the middle of a long day in the garage.

It could be a poorly ground ring and gear set or perhaps there is a burr I have missed. I will cross that bridge when I get there.

I did get an ultra-solid backlash on Run 'B'. So I am leaning more towards the carrier shim stacks, and preload problems causing my abnormal backlash issues.
This is where I am wondering if I did miss a burr or perhaps the ring gear(most likely pinion) is giving me inconsistent backlash from tooth to tooth. I spent the time and measured all of the teeth just before making my final change to the backlash before running pattern 'D'.

I found that there was a variance of roughly ~.004" in the runout of the ring gear. I am not sure if I am using that term correctly. Basically the height of the teeth 'wobbles' ever so slightly as the gear rotates around. It is a USA Standard Gear sourced set, that is not a premium level ring gear. I'm not convinced that this level of variance is even an issue. I would think that some of this variance will work itself out in the break-in period.

Does anyone know if this is something that works itself out during the break-in period?

I'm obviously not gonna throw anything in the trash here, but it was something I looked into.


Anyway, the pattern is closer to ideal and I figure I'll have it sometime tomorrow or the next day. Time for bed.
 

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It's 6am. You made gains. Hope you slept well, I did. Probably the first time in a week. You are on the right track. Slow and steady wins the race. ??
 
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