Screwed up my 12 bolt

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1low4x4

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I get that, but I don't see any "thin" or thick indications, only 3 or 4 series carrier. So if a 2 series carrier is 3.42 to 2.73 and what I have and isa 3 series carrier thats good for 3.73 and numerically higher, then what the heck is a 4 series for?
 

Jrgunn5150

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I don't know what a 2 series is, but 3 series is 2.76-3.42. 4 series is 3.73 and up.
 

1low4x4

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oh. **** so much different info online lol.
 

Jrgunn5150

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oh. **** so much different info online lol.

I looked, and the 2 series was for car's with the stupid gas crunch ratios they had back then like 2.26.
 

1low4x4

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ok. Then I need to order for the 4 series. looking into that now
 

crazy4offroad

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The most common guess for these trucks is 3 series for the 12-bolt and for a majority of them they ran 3.08s. Most 80s-up models started moving to the 10-bolt. But I had forgot you had an aftermarket Eaton in it, will be hard to tell without measuring it, or checking the existing ring gear or locker for a model number and see if you can run it down that way.
 

crazy4offroad

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I get that, but I don't see any "thin" or thick indications, only 3 or 4 series carrier. So if a 2 series carrier is 3.42 to 2.73 and what I have and isa 3 series carrier thats good for 3.73 and numerically higher, then what the heck is a 4 series for?

If you have a 3 series carrier (2.73-3.42) and you want to run a gear higher than 3.42 you can usually find a "thick" gear set to get you there. 4.10s for a 4 series carrier isn't necessarily "thin", just "normal" thickness. Just for comparison it would be impossible to run 3.08s in a 4 series carrier because it truly would be "too thin".

So when you see "4.10 for 3 series carrier" it is likely a thick gear set. If it was me I wouldn't order anything until you're 100% sure what's in there. Return shipping/restocking fee can be expensive for a R&P set.
 

Jrgunn5150

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If you have a 3 series carrier (2.73-3.42) and you want to run a gear higher than 3.42 you can usually find a "thick" gear set to get you there. 4.10s for a 4 series carrier isn't necessarily "thin", just "normal" thickness. Just for comparison it would be impossible to run 3.08s in a 4 series carrier because it truly would be "too thin".

So when you see "4.10 for 3 series carrier" it is likely a thick gear set. If it was me I wouldn't order anything until you're 100% sure what's in there. Return shipping/restocking fee can be expensive for a R&P set.

Precisely, for all I know you have a 3 series Eaton, with a thick 3.73 on it.
 

1low4x4

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Thanks for the help guys. The really cool thing is that I got this axle for like 50 bucks from a friend and discovered the eaton in it that he didn't know it had lol. Ordering 4.10s and install kit now
 

1low4x4

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Well the ring and pinion and install kit worked great. The yoke didn't. And I didn't check it before installing it so im out 100 bucks, my caps were too big too fit in it evenm though I measaured them before hand and chose what I thought was the right yoke. Had to go back to the old yoke. But I found out why I lost all my fluid. Idk what the yoke came off of but a 12 bolt seal would fit the housing but not the yoke. Then another seal would fit the yoke but not housing. I got a good guy at oreillys that pulled the book out, and after measuring the yoke and the housing we matched it up to a bastard size seal that worked.

basically they had a seal that fit the housing but was way too small for the yoke. the yoke ripped it when it was put in and that's how it lost the fluid over time
 

crazy4offroad

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Was the diameter of the caps too big or the length of the cross too long to go in the yoke? Sometimes a needle bearing will fall into the bottom of the cap and make the cross too long. I thought 1330 was odd for your truck, it's usually 1310 or 1350. Just about have to use a digital caliper micrometer to get accurate measurements for some of these things. Did you install the gears yourself?
 

1low4x4

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I have a digital caliper that I used. The overall length of the ujoint fit the yoke, just the caps were to big in diameter. yeah I did the gears myself. I was able to match up existing shims pretty much and check from there. Everything works good
 

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