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Srw to drw swap info needed.

Discussion in 'Differential & Driveline' started by 5akman, Sep 19, 2019.

  1. 5akman

    5akman Full Access Member

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    Looking to swap out the 14 bolt semi float in my 1984 k20 for a full float dually axle. I've found one from a 1981 1 ton dually, will that fit? With what mods? New springs perch locations? Or, what dually axle would be a direct bolt in, if any?

    Lots of confusing info via the search tool regarding perch widths, wsm to wsm etc.....
     
  2. nvrenuf

    nvrenuf Full Access Member

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    A dually axle will be from a 1 ton, shock brackets and spring perches are different on 1 tons vs 1/2 & 3/4 tons.

    Is the dually axle from a square body? A pick up or a cab & chassis? A pick up axle is extra wide at 74" WMS and a cab & chassis axle has 63" (iirc) WMS whereas an SRW axle is around 67" WMS.
     
  3. TubeTruck

    TubeTruck Full Access Member

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  4. nvrenuf

    nvrenuf Full Access Member

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  5. 5akman

    5akman Full Access Member

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    It's out of a pick up and I was just assuming that a factory dually would be a full float. The axle has hub caps on it so I can't see the end of the hub to check semi vs full. But according to the info in this thread, it would be a semi float?

    So, what's my next best choice to look for?
     
  6. TubeTruck

    TubeTruck Full Access Member

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    I did some more research and you are correct. :) From what I just read, I didn't realize the DRW 14 bolts only came on Vans and the rest of the DRW are pretty much Dana 70's. Learn something new every day :)
     
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  7. nvrenuf

    nvrenuf Full Access Member

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    No semi floater daully axles from GM. An SRW full floater hub will accept a factory hub cap but a dually hub wont, it's too long.

    To be clear; are you just wanting a 1 ton axle or a really wide 1 ton axle or are you converting to dual tires?

    You can find DRW 14 bolts that are wide like the square body D70HD's in the GMT 400 trucks, they are 72"~74" wide like the D70HD. I'm a fan of the D70HD just because of the beefy housing and internal parts but you can't beat the 14 bolt for ease of gear set up and "dime a dozen" price.
     
  8. 5akman

    5akman Full Access Member

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  9. nvrenuf

    nvrenuf Full Access Member

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    I gotcha. That said, I'd suggest you do some measuring before you buy, there's a significant width difference between DRW pick up and c&c axles. A pick up axle might place the outside tires beyond the side of the bed. Just saying it out loud.
     
  10. 5akman

    5akman Full Access Member

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    I've got a f
    I've got a full 8' wide flat bed so I think I'll be good there. I'm wondering more about spring perch widths and the inside width between the inner tires, no chance of rubbing on the frame?
     
  11. nvrenuf

    nvrenuf Full Access Member

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    If you get a D70HD from a square body pick up then there's no worries about it fitting under the frame etc but you will have to move the spring perches and shock brackets.
     
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  12. 5akman

    5akman Full Access Member

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    Will I need to worry about the front axle width if I go with a dually rear? When going with one of the add on dually kits with spacers, do they also widen the front axle WMS? I want to make sure I don't create additional issues when going with a dually rear (dually tires) and keeping the stock front axle.
     
  13. nvrenuf

    nvrenuf Full Access Member

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    I don’t know if anyone makes dually conversion parts for a front 10 bolt. Personally, id question if the bearings in the 10 bolt can tolerate the heavy offset of the dually wheel.

    I’d suggest running a standard wheel until you can source a dually version D60.
     
  14. TubeTruck

    TubeTruck Full Access Member

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    Too bad you don't live in Illinois. There are tons of DRW Front Dana 60's for sale here for about $500. No standard Dana 60 though. I'm about to buy a couple and convert them to singles.
     
  15. ajdemello

    ajdemello Full Access Member

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    Really? I gave 800 for my d60 drw and 4.56s. I thought I did ok guess I should have come south.
     

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