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Conversion joints needed?

Discussion in 'The Garage' started by sope, Nov 1, 2006.

  1. sope

    sope 1/2 ton status

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    Mabey this is a nube question but I often see advice on when conversion joints are needed and when spring perches need to be moved to go with a one ton drive train in a half ton. I have only done this once but I have an 87 V1500 shortbox and I upgraded to a 14 bolt ff and a D60. I didn't have to move spring perches or use conversion joints. I don't need this information for my build. I'm just currious and I'm sure other guys that are upgrading are too. I can't remember what years my one ton's came from but everything bolted in. I have 1350 rear joints that were for my 10 bolt and my 14 bolt. I check some vender web sights like Summit and the U joints seem to usually be 1350's in both 1/2 ton and 1 ton trucks.

    I guess I was lucky and I'm sure conversion joints and spring perches have to be moved often but when? :confused:
     
  2. Hossbaby50

    Hossbaby50 3/4 ton status

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    Napa #447 ujoint is to convert from a 10 bolt rear axle to a 14bff rear axle. Front ujoint should still be the same on the front driveshaft.

    Harley
     
  3. Hossbaby50

    Hossbaby50 3/4 ton status

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    Oops, I just noticed you have an SM465 which means you already should have a 1350 ujoint on the rear driveshaft so you should not need a conversion ujoint to attach your rear driveshaft to a 14bff.

    Harley
     
  4. goldwing2000

    goldwing2000 Guest

    Most 10-bolts come with S44 joints and 12 bolts come with 1310 joints, unless (as Hossbaby said) you have the SM465. And even that's not guaranteed. I had a 12-bolt behind an SM465 that had 1310 joints. It all just depends on year and equipment.

    Also, the 14bff you got must have been off a 3/4-ton and not a 1-ton, since the 3/4 and 1/2 ton share the same spring spacing. The 1-ton axles have narrower spring perches to accommodate the DRW option.

    It's also possible that your p.o. changed things around.
    All in all, you just got lucky with your upgrades! :waytogo:
     
  5. Hossbaby50

    Hossbaby50 3/4 ton status

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    The SM465's with the 1350 ujoint are from the 208/241 era trucks with 10 bolt axles. The older Sm465's had different joints like you mentioned.

    Harley
     
  6. goldwing2000

    goldwing2000 Guest

    Mine was in the transition period. It was an '80 with a 205 case, 10-bolt front, 12-bolt rear and 1310 joints throughout.

    I never broke anything on that thing but wore out my share of u-joints. :D
     
  7. sope

    sope 1/2 ton status

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    Thanks for the info.
    I got it now. The SM465 208 is the difference and a bolt up. The duall rear wheel diffs have the different spring spacing.
    I've been wondering about this for a while.
     
  8. dremu

    dremu Officious Thread Derailer Premium Member

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    Uhh, not quite.

    1-ton frame are narrower, so any 1-ton rear axle, whether SRW or DRW, would have the funny perches.

    Some people think one tons are always dually, and in 73-87 this ain't the case -- lots of C/K30 SRW's out there.

    -- A
     
  9. goldwing2000

    goldwing2000 Guest

    Yep. That's pretty much what I said back on post #4. All 1-ton axles have narrower perches to accommodate the ones that have the DRW option.
     
  10. dremu

    dremu Officious Thread Derailer Premium Member

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    Yep. Just trying to be extra precise, for future generations of people reading this :)

    -- A
     
  11. sope

    sope 1/2 ton status

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    Thanks.
     

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