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Anybody runnin 2 1/2 ton axles?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by bigk, Sep 2, 2001.

  1. bigk

    bigk 1/2 ton status

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    Alot of people say they are cheaper than D60's, how tough are they to install, and are they really heavy?

    Karl
    Temporarily Unemployed Underwear Model
    87 3/4 ton
     
  2. DesertDueler

    DesertDueler 1/2 ton status

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    I have been wondering the samething. The only I know about them is they are really heavy, and I believe they use air brakes.

    86 Jimmy 4"lift 35"MTRs Other cars 69Firebird w/525 hp,and 70GTO live in PHX,AZ<a target="_blank" href=http://www.geocities.com/modifierperformance>My vehicles</a>
     
  3. fender

    fender Registered Member

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    I believe a rear 2 ½ Rockwell is about 150 pounds heavier than a 14 bolt, and a front one is about 100 more than a dana 60. I'm pretty sure that they don't use air brakes. Jeff (Jeff247?) has some under his mud truck.

    -fender-
     
  4. michaelm

    michaelm 1/2 ton status

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    they are cheap....with 6.72 gears. i know someone with stacks of converted Unimog axles for sale but they are some like 7.40:1. great for off road use but not so highway friendly
     
  5. Pugsley

    Pugsley 1/2 ton status

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    Some use air brakes, but most are hydraulic.

    1 tequila 2 tequila 3 tequila Floor
    <a target="_blank" href=http://pugsley.alloffroad.com>pugsley.alloffroad.com</a>
     
  6. bigk

    bigk 1/2 ton status

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    Couldn't you just put in an overdrive to make up for the low gears?

    Karl
    Temporarily Unemployed Underwear Model
    87 3/4 ton
     
  7. michaelm

    michaelm 1/2 ton status

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    6.72 * 0.80 = 5.376 that covers typical OD gears so lets say you are rich and can afford an overdrive tranny with an aftermarket OD box like a Gear Vendors, or Ranger, or USGEAR that gets you 5.376 * 0.80 = 4.30. so yes if you get double overdrive you could run them easily on the street with 35s and up. my choice would be ranger in front of NV4500
     
  8. DesertDueler

    DesertDueler 1/2 ton status

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    You would need overdrive and some big tires. If you use a 700r4, Unimog axles with 7.40 gear ratio, and 44 inch tire, your rpms in overdrive at 55 mph would be 2175 rpms. That wouldnt be bad, but the tranny would never last turning those big tires and those huge axles. Would be cool though to cruise with 7.40 gears.

    86 Jimmy 4"lift 35"MTRs Other cars 69Firebird w/525 hp,and 70GTO live in PHX,AZ<a target="_blank" href=http://www.geocities.com/modifierperformance>My vehicles</a>
     
  9. Jeff427

    Jeff427 1/2 ton status

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    Yes, we (my cousin and I) installed a set of old GMC 2 1/2 ton axles in a 77 Chevy 3/4 ton. The front axle was bolt in (the spring pads lined right up with no modifications). The steering took some engineering to get it to work. The rear axle we had to modify a bit more, because they have strange spring pads on the rear axles. Oh and the front axle is reverse rotation (not reverse cut) so you have to use the GMC transfercase, unless you flip the center section in the front axle (which is easy, they unbolt, like a furd 9 inch). They have air over hydraulic brakes, which means the braking system on the axle is hydraulic, so it could be set up to run off your master cylinder (in theory anyway).

    Jeff427
    <a target="_blank" href=http://muddog.off-road.ws>Mud Dog Off Road Club</a>

    <a target="_blank" href=http://lyonsdesign.bizhosting.com>Lyons Design Web Site</a>
     
  10. Jeff427

    Jeff427 1/2 ton status

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    Oh, and the GMC axles that we have are geared 6.17.

    Jeff427
    <a target="_blank" href=http://muddog.off-road.ws>Mud Dog Off Road Club</a>

    <a target="_blank" href=http://lyonsdesign.bizhosting.com>Lyons Design Web Site</a>
     

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