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12 bolt strength?

Discussion in 'The Garage' started by lochenjons, Jan 31, 2007.

  1. lochenjons

    lochenjons 1/2 ton status

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    How does my '77 12 bolt compare to good ol' 10b and 14b? Isnt it about the same as a newer 10b? I think that's what I heard
     
  2. Confedneck79K30

    Confedneck79K30 3/4 ton status

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    its marginally stronger than a 10 bolt, ya know, a 10 bolt can hold up to 31s with 35 psi, but a 12 bolt can hold up to 31s with 31 psi...
     
  3. boggerless

    boggerless 1 ton status Premium Member

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    mine holds up to 36.5s at all psi's.for 12 years.:D
     
  4. bbck5on37s

    bbck5on37s 1/2 ton status

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    I would go with a 14bff...they are a dime a dozen and very strong
     
  5. 87BrnRsd

    87BrnRsd 1/2 ton status

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    Its pretty comparable in strength to a 10 bolt. It is nowhere near even close to a 14ff. 14ff= 10.5" ring gear, and a full floating design. 12b= 8.875" ring gear, and semi floating. and thats just the basics
    -harrison
     
  6. boggerless

    boggerless 1 ton status Premium Member

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    rocks or mud??mud you can be an asshole and win.:haha: weight is the thing in the mud.rock? i could not tell ya!plus it helps toknow what to do.:laugh:
     
  7. chris walker

    chris walker Registered Member

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    12 bolt good for 33 in all conditions sf14 bolt good for 37 in all conditions ff14 good from 33-44 in all conditions
     
  8. boggerless

    boggerless 1 ton status Premium Member

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    i'm in mud mostly so it works good for now.:D
     
  9. AZ79K5Project

    AZ79K5Project 1/2 ton status

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    This discussion comes up daily. Search a little and you find all kinds of opinions. The popular view is upgrade to a 14bff. Here's another recent discussion Click

    The cost of a 14bff is super cheap. Now add the cost of the 8 lug outers for the front. If you go to a bigger tire to regain the clearance lost by the bigger pumpkin, you will have to swap out the front to a D60. Now big $$$

    There are some bullet proof rigs on this site built right for serious crawling. :bow:
     
  10. lochenjons

    lochenjons 1/2 ton status

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    Yeah I know 14ff is the way to go. This is actaully why I ask because I found one for cheap(ish) but wasnt really planning the swap for later and wondering as to how much success other people have had with the 12b to see how long I could run it with worrying too much about breakage
     
  11. AZ79K5Project

    AZ79K5Project 1/2 ton status

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    It depends on your driving style, right foot pressure. A lot of guys are running 12 bolts with 33's and 35's without problems. They carry extra shafts "just in case."

    I'm personally staying with 10 front and 12 bolt rear. I'm upgrading shafts and calling it good. Nothing is ever bullet proof. The tallest tire I will run is 35 or 37. I'm in the minority opinion staying stock and throwing a little money into it.

    Anyone else want to chime in???
     
    Last edited: Feb 1, 2007
  12. Hossbaby50

    Hossbaby50 3/4 ton status

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    1/2 ton axles can be totally servicable in a wheeling truck up to about 37" tires max. 35" is a good size for keeping breakage to a minimum. The AZ guys have learned recently that on a fullsize truck with built 1/2 ton's 37" is about the limit for hard wheeling. I have seen 3 snapped Chromo D44 stubs, 1 twisted shortside D44 inner, several twisted 12 bolt housings & chromo axles, along with other major breakage. Keep in mind that most of these trucks are in the minority of wheelers. They are trucks that are rockcrawled to the fullest extent of there limitations.

    If you are a moderate wheeler and only plan on 35" tires then put a set of chromo shafts in the 12 bolt and wheel it. Chromo rear shafts are not as much money as many think. They will cost you less then a 14bff & will get you on the trails sooner. You should get plenty of use out of it under all but extreme conditions if the diff is in good shape.

    Harley
     
  13. UPS

    UPS 1/2 ton status

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    I have 35" boggers on my 12 bolt and haven't had any problem running it in the mud, but the 305 doesn't have any power and the 700r4 slips.

    I have a very heavy right foot, but I don't get after it in hard ruts.

    I also haven't had any problems with the 10 bolt front.

    I think it would be a different story if the truck had some power.
    Mike
     
  14. NEK5

    NEK5 3/4 ton status Premium Member

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    I`m only running 33"s, and looking for an axle upgrade out back... How does the 12b compare to the 14bsf? Is the 12b a worthwhile upgrade, with me only running 33s? The only wheeling I do really is mud...
     
  15. Hossbaby50

    Hossbaby50 3/4 ton status

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    A 14bsf is better/stronger then a 12 bolt.

    Harley
     
  16. AZ79K5Project

    AZ79K5Project 1/2 ton status

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    The 14bsf is a 9.5 inch ring gear, the 12 bolt is a 8.75 inch ring.

    Here is an axle chart with some information.

    Axle (Large).jpg

    Axle (Large).jpg
     
  17. NEK5

    NEK5 3/4 ton status Premium Member

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    I think the SF is the way to go, but I would need it in 6 lug, which I might as well go discs, which would convert it to 6 lug...
     
  18. Hossbaby50

    Hossbaby50 3/4 ton status

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    There are 6 lug 14bsf axles out there under light duty 3/4 ton Chevy's from 88+. You will have to move the spring perches for them to fit but they are out there & work. A 14bsf is a better choice then a 12 bolt if you can get one & are looking to stay 6lug.

    Harley
     
  19. bigblazer87

    bigblazer87 1/2 ton status

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    Yep, that's what I'm doing (6 lug 14SF).
     
  20. big dan

    big dan 1/2 ton status Premium Member

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    If your wanting to upgrade go with the 14bsf or 14bff. IMO going from a 10b to a 12b is a waste of time and money.
     

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