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How durable is the 14 bolt SF rear axle?

Discussion in 'Differential & Driveline' started by Bob Igram, Aug 8, 2019.

  1. Bob Igram

    Bob Igram Junior Member

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    Ive been looking at an 1984 K2500 Suburban, its got the semi floater rear, its lifted with 35", tires, an automatic, and a 454 that might have been lightly built...........Presumably it ran a trail similar to the Rubicon, or thats the rumor! How much of a weak link is this axle, especially in low range?
     
  2. skysurfer

    skysurfer Full Access Member

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    Mine has held up well. I've run mine pretty hard taking clients up a steep dirt Forest Service access road for twenty years. It's a 4000 ft. climb in 4-Lo with over 3000 lbs of people and gear. Only issue I've had is some seepage at the axle tube welds. Not enough to drip, it just gets damp and collects dust. If the right full floater comes along I'll make the swap but I have no problem running the SF until that happens.

    The first minute of this video shows the workload I'm talking about, the rest you can skip unless you're bored.
     
    Last edited: Aug 8, 2019
  3. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    All my opinion, and experience-


    Its strong. If it has a Gov lock(limited slip), then that is a time bomb. It is not if but when it goes.

    Avoid the burnouts, donuts, and teenage things if it does have one. Then it will last quite a while.

    It's why I have a FF now.
     
    Last edited: Aug 9, 2019
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  4. Bob Igram

    Bob Igram Junior Member

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    Thanks John and Brent........It sounds like a respectable unit, and my years of teenage behavior are MOSTLY past. It might serve my purposes well. If i decide to get it, i will check and see if its got the Gov Lock.......I did look at it a month ago, and it had the underhood sticker on the drivers side fenderwell that listed factory options
     
  5. yevgenievich

    yevgenievich Full Access Member

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    Gov lock on 14 bolt sf is stronger than the famous 10 bolt version. It is a decent axle depending on use. Bigger than 35's coupled with rock bouncing have higher chance of breaking it.
     
  6. eskimomann209

    eskimomann209 Full Access Member

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    Yeah what he said. The 10 bolt version is the “ ticking time bomb”
    I have 35x13.5xr20 and we shit and get n burn out enough to say it’s a solid axle.
    I trust it very much.
     
  7. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    Of course it is stronger than the 10 bolt and most definitely a solid/strong differential.

    But it is a Gov Bomb in either diff. Hell, maybe it lasts a lifetime.

    I went through two, mild off roading only at the time. Bind it up and wait for the boom.

    I know my front 10 bolt is now my weakest link, so I take care as not to bind it up in the rocks.

    Hence why I told him to avoid all the shenanigans if he wants it to last, just treat it well, and know the Gov lock is the weak link to that diff. Avoid binding it up.

    @eskimomann209 You have 35x13.5x20. Maybe you dont have enough sidewall to pull the pin on the Gov bomb, or haven't left the mall? Lol, all in fun.
     
    Last edited: Aug 9, 2019
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  8. RoryH19

    RoryH19 Full Access Member

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    I'll be doing this swap soon. My factory 10 bolt with 3.08 to 14 bolt SF 6 lug 3.73 with gov lock.
    Not only is this a better axle than the original it's wider so the front and rear tire widths match.
    Looks do matter too :)
     
  9. eskimomann209

    eskimomann209 Full Access Member

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    Have you seen my mall?
    Those parking space concrete wheel stops are big ole boulders. I crawl up them every day. And those decorative pebbles err I mean boulders!
    Haha
    No I mud and do some hills but it isn’t a rock crawler.
    Mine is in a 98 SAS c1500 though
    Axle was removed from a 93 k1500”HD”
    And I also pause for dramatic effect.
    Did a rear disk conversion on it
     
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  10. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    Respect for any SAS.

    At the rate malls are failing. They may become a place to really crawl.


    Now get somesidewall, and all will be right in the world. Lol

    I wanna go back to the days of 44s on 15" wheels. Now everything caters to a 17" rim.
     
    Last edited: Aug 9, 2019
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  11. eskimomann209

    eskimomann209 Full Access Member

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    Shit if I could afford larger tires I’d have them already!!!
    Between the square and the gmt400 money is currently being funneled into the square
     
  12. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    Gotta give you shit. Lol

    Just dont squat it!

    The fact you take out and use it, for mudding, and hills is a huge ass win in my book.

    All these new trucks with lifts, and either street tires, or less sidewall than you make me laugh.
     
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  13. eskimomann209

    eskimomann209 Full Access Member

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    No worries brother I’m always happy to read messages from you. Means you’ve managed to tear yourself away from your sex and the city collection long enough to read the threads
     
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  14. eskimomann209

    eskimomann209 Full Access Member

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    Yep. They spend More money on powder than my whole trucks valued at. But they can’t / won’t play with the trucks!
     
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  15. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    LoL. Gotta go collect some more of the city's hearing soon. You know, cause of those 4' straights.
     
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