Nashville TJ's Build - Continued

Gotta love the pinion shims on these. Does your axle weep 90wt around them? The 78 14bolt i put in my 70 k20 has always done that. Not enough to be anything but a slight oil stain but still an annoyance on an otherwise leak free axle

Mine have always been dry. Like you, I always assumed they would given there is no sealant there. I guess if the shims and sealing surfaces are in good enough shape they should not leak.
 
Here is the pinion gear from the last setup.

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Edit: Disregard this post. Bad pattern. Reason: I'm an idiot...

Still trying to bracket the setup. Reduced the pinion shim to 12 thou (increasing the pinion depth), and 5 thou backlash.

IMG_5381.JPG


IMG_5382.JPG


This one confuses me, as I went deeper, but the pattern (to my eye anyway) looks shallower.
 
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Here's the tough part about reading patterns, Ryan. Can you tell which one of these matches my pattern? I really can't. Also, context is important. I think this is a standard pinion setup, like a 60 or a 44, meaning increasing the pinion shim increases pinion depth. On the 14 bolt, increasing the pinion shim decreases pinion depth. So it's definitely hard to understand what this is telling me to do.
 
OK - I figured out my confusion from that last pattern. I had forgotten to tighten the carrier bearing caps after adjusting the backlash. It's the little things that are important... :rolleyes:

Anyway, this is the real pattern at 12 thou pinion shim and 5 thou backlash. This makes sense as the pattern now looks deeper as I expected.

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I'll wait for some feedback on this one before proceeding. To me, the drive side looks good, but the coast side looks deep.
 
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Here's the tough part about reading patterns, Ryan. Can you tell which one of these matches my pattern? I really can't. Also, context is important. I think this is a standard pinion setup, like a 60 or a 44, meaning increasing the pinion shim increases pinion depth. On the 14 bolt, increasing the pinion shim decreases pinion depth. So it's definitely hard to understand what this is telling me to do.

I think all of your patterns look like the 3rd row (drive side biased toward heel with flat line at top and coast biased towed toe also with flat line at top): pinion depth too shallow as you said (meaning need less pinion depth shims as you also said). But I too am confused by the last pattern which looks more shallow the the second. So... 0.052=way too shallow, 0.032 less shallow, 0.012 back to way too shallow?

Nevermind. Just saw the last post. Now its a little deep so you have the bracket!
 
OK - I figured out my confusion from that last pattern. I had forgotten to tighten the carrier bearing caps after adjusting the backlash. It's the little things that are important... :rolleyes:

Anyway, this is the real pattern at 12 thou pinion shim and 5 thou backlash. This makes sense as the pattern now looks deeper as I expected.

View attachment 587680

View attachment 587681

I'll wait for some feedback on this one before proceeding. To me, the drive side looks good, but the coast side looks deep.

The patterns are pretty centered heel to toe. Seems like 2 possibilities: 1) add back 1-2 thou pinion shim or 2) open up backlash by1-1.5 thou? What's the backlash spec?
 
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Here's the tough part about reading patterns, Ryan. Can you tell which one of these matches my pattern? I really can't. Also, context is important. I think this is a standard pinion setup, like a 60 or a 44, meaning increasing the pinion shim increases pinion depth. On the 14 bolt, increasing the pinion shim decreases pinion depth. So it's definitely hard to understand what this is telling me to do.

Looks like you're getting it squared away but yes I'd be less worried about if it says increase or decrease shims but pay attention to which way it wants it to move since different axles do need different adjustment types.
 
The patterns are pretty centered heel to toe. Seems like 2 possibilities: 1) add back 1-2 thou pinion shim or 2) open up backlash by1-.5 thou? What's the backlash spec?

Backlash spec on the 14 bolt is 3-12 thou, with 5-8 thou being best. I'm trying to stay on the tight side of the range to help a bit with strength - but only if the pattern supports it.

Edit: Jeeze, I can't believe I typed that. Help a bit with strength - ON A 14 FREAKIN' BOLT!
 
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Looks like you're getting it squared away but yes I'd be less worried about if it says increase or decrease shims but pay attention to which way it wants it to move since different axles do need different adjustment types.

That was actually the problem with that chart - it never indicated if you are shallow or deep, or whether to increase or decrease pinion depth - just what to do with your shims. Funny thing was it was specific on what to do with backlash.

I have a couple of charts I'm using. The Yukon chart is pretty good, with good guidance.

But more importantly - I have you guys. :love:
 
That was actually the problem with that chart - it never indicated if you are shallow or deep, or whether to increase or decrease pinion depth - just what to do with your shims. Funny thing was it was specific on what to do with backlash.

I have a couple of charts I'm using. The Yukon chart is pretty good, with good guidance.

But more importantly - I have you guys. :love:

You can tell direction by what the pictures show. Which way does the pattern need to move, move the pinion accordingly.

There used to be a really nice guide on Randy's ring and pinion but it's long gone.
 
Having built many engines and a few manual transmissions over the years, but not yet done a re-gear, I really enjoy these threads! Before the Internet, I either had to find a guru to learn from, read a book (hard to find one that answers all my questions), or wing it. Winging it is a good, but expensive (time and money) way to learn. The Internet was a game-changer for me!
 
Subaru people. :sneaky:

This one really got me 🤣

We're lucky to be able to experience so many other people's perspectives across the internet and forums.

I'm classically a reckless dude, and it is very good for me to read threads like this for example. I can tell myself "if I go into my regear like I was trying to write a thread like Jeff's, I'll be much more careful and methodical and do a much better job."

Thanks Jeff and others for showing me how to not be a reckless idiot about things.
 
This one really got me 🤣

We're lucky to be able to experience so many other people's perspectives across the internet and forums.

I'm classically a reckless dude, and it is very good for me to read threads like this for example. I can tell myself "if I go into my regear like I was trying to write a thread like Jeff's, I'll be much more careful and methodical and do a much better job."

Thanks Jeff and others for showing me how to not be a reckless idiot about things.
lBasket, it's good to recognize that. Recklessness and precision work don't mix well. I've mentored a lot of engineers over the years, and my observation is that recklessness is actually just a manifestation of impatience. If you can learn to temper your impatience, you can learn to do quality precision work.

Just don't ask me about patience as applied to learning to be a great welder. That's been the most frustrating experience for me over the years, and I'm not a newbie. I bought my Millermatic about 35 years ago. I think my problem is I'm blind and just very uncoordinated, and welding requires good eyesight and good coordination (muscle memory?).
 
One other thing, and I've said this before. I'm amazed every time I log in here at what I can learn! The collective knowledge of the group is astounding. Most forums are horrible in that respect. I've only ever experienced an Internet forum full of experienced people so willing to share knowledge one other time. Chris has created an incredible resource for us TJ nuts!
 
lBasket, it's good to recognize that. Recklessness and precision work don't mix well. I've mentored a lot of engineers over the years, and my observation is that recklessness is actually just a manifestation of impatience. If you can learn to temper your impatience, you can learn to do quality precision work.
Yep, you hit it right on the head there! I do tend to be impatient. I am getting much better about it. Working on things that need to be precise (jeep/car stuff are definitely big ones) and finances are where it has made huge changes. But it has also made driving in traffic or waiting in line at the grocery store much better - it's hard to enjoy much, or spend time to do things well, when you're in a hurry!

I do read your thread as well and sometimes think "wow idk if I could ever pay this much attention to detail" haha, but even even if I don't get that far it shows me that some do, and the results it gets you (spoiler: they're good).

Slow is smooth, smooth is fast and whatnot.
Just don't ask me about patience as applied to learning to be a great welder. That's been the most frustrating experience for me over the years, and I'm not a newbie. I bought my Millermatic about 35 years ago. I think my problem is I'm blind and just very uncoordinated, and welding requires good eyesight and good coordination (muscle memory?).
Haha! I am a booger welder extraordinare so I'm in the same boat here. Luckily for me being terrible at it slows me down where I otherwise might not 🤣
 
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Having built many engines and a few manual transmissions over the years, but not yet done a re-gear, I really enjoy these threads! Before the Internet, I either had to find a guru to learn from, read a book (hard to find one that answers all my questions), or wing it. Winging it is a good, but expensive (time and money) way to learn. The Internet was a game-changer for me!

I was lucky that when I got my mentoring on gear setup I had a 30+ year experienced tech showing me the ropes. I'd taken a college course on manual & automatic transmission rebuild while I was stationed in Korea but all we had were a few cutout models that the college had. The other sad part was that I knew more than my instructor about 60% of the time.

I got hired at this Ford garage and they made me the regear person so I got sent to a Ford school and then when I came back they had their old tech come in for 2 weeks and tech me the finer points of setting up gears. But this was 30 years ago now and prior to when I was wounded so I've forgotten a lot of what I'd learned back then. I can still do my own gearing but I'm not versed well enough anymore to offer advice.

Jeff,
You're getting CLOSE that I can offer but I'd wait for the more experienced to chime in. There is a good FB group for this sort of thing.
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