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why centered rear?

Discussion in '40- & 55-Series Tech' started by rusmannx, Sep 2, 2003.

  1. rusmannx

    rusmannx

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    i've been reading about the different axle options out there, and people are talking about centered center-sections.

    what is the benefit of this setup?
     
  2. bad_religion_au

    bad_religion_au

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    don't know much, i assume you mean centered rear diff, or am i way off base.

    some axles are stronger than stock that come with a centered rear diff,

    on the other hand, people go for a centered diff when doing transfer case and drivetrain swaps that have a centered output on the T case, whereas stock, cruisers have an offset transfer case.

    something like that
     
  3. woody

    woody Internet Fireman Staff Member

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    few t-cases have offset rear outputs like the Cruisers....which limits your options for gearing and axles. Getting into the "big" HD stuff usually means either running a centered rear diff or getting one custom made...and custom = more $$$ plus tougher-to-find replacement parts.
     
  4. bad_religion_au

    bad_religion_au

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    that'd be what i was trying to say
     
  5. rusmannx

    rusmannx

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    if i'm staying with the orig tcase, and want to have cut down 60's or something, would i want to leave the rear diff inline with the tcase?
     
  6. woody

    woody Internet Fireman Staff Member

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    the BEST way is to keep the rear diff pinion in line with the t-case output. There are people who run a centered diff with offset t-case, and a centered t-case with offset diff. The "experts" say it can be done, but the compound angles are tougher on driveline components. They should at least be "close" to inline.

    I do know of people who have done it in stages...installing 60 axles with the rear centered then doing the centered t-case later.
     
  7. rusmannx

    rusmannx

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    thanks for the info.

    if i did find myself a pair of 60's or 9" axles, what all has to be done to cut them down from full size?
     
  8. dinkleberry

    dinkleberry

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    Believe it or not some local machine shops can do it.

    I had a little shop here make a narrowed 9" for a pro street car.

    I bought custom axles. He cut tubes and welded all the mounts.

    Probably not a DYI first timer kinda job. I'd check the hardcore threads. :D
     
  9. rusmannx

    rusmannx

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    so i have to
    1. tear the axle apart
    2. have the tubes cut
    3. have the shafts cut

    does anyone know a site that lists all of the year/make/models that 35 spline D60's were used?

    i have some connections at the local places, and i think i can find me a set for a good price... i just don't know what to tell them i am looking for (year/make/model wise that is)
     
  10. dinkleberry

    dinkleberry

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    I've got a j#@p guy who showed me a link of exactly what your talkin about. I'll try to find it and get back to you.
     
  11. cruiserrg

    cruiserrg

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    If you are looking for a full floater Dana 60 rear, 35 spline will be hard to find, most are 30 spline and less than 1.5 in dia. You can however find some rear Dana 60s that were offset some, I am told usually on vans.

    Another option would be a 14 bolt. It is considered a centered diff, but the pinion is offset some, and one axle is shorter than the other. It's only a couple of inches but may be worth a look at as the axles are 1.5 30 spline. You also can find 14 bolt cab and chassis rea ends which have a narrower WMS to WMS at about 63" and better suited to cruiser width (unless full width is what you are looking for)
     
  12. rusmannx

    rusmannx

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    i would like to take them down to 55 inches (stock 40) wide.
    i didn't think about a 12 bolt, but that is a good idea.

    what about the front axle?
     
  13. cruiserrg

    cruiserrg

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    [quote author=rusmannx link=board=1;threadid=4879;start=msg37364#msg37364 date=1062557583]
    i would like to take them down to 55 inches (stock 40) wide.
    i didn't think about a 12 bolt, but that is a good idea.

    what about the front axle?
    [/quote]

    I actually mentioned 14 bolt, 12 bolt would not be as strong. Custom built to cruiser width axles will take a bit of doing and prolly a lot of $$$. I guess I need a bit more information for why the axle upgrades. Are you planning to go to bigger tires? What type of wheeling do you do? Basically whats your reason?

    I think the stock axles are fairly tough when running 35s or smaller. If you wheel hard like I do, maybe put some longfields in the front and call it good. Now if you are talking 38s+ and heavy rock crawling, then you need to look at a Dana 60 front. I see no reason to change the stock front end unless your set on 38s+ or competition use. Some people have looked into Dana 44 front axles to get away from birfs, but with aftermarket birfs available there is no need.
     
  14. rusmannx

    rusmannx

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    oh yes, 14 bolt... sorry about the mistake.

    well,
    right now i'm stock on 33's. i pretty much travel the mountin trails in search of mud holes. i haven't done much rock crawling (moab is 3 hours away though, so i'm thinking of trying it out.

    i'm planning on going to 36's when i SOA this winter (assuming everything goes well between now and then).

    the thing is, i figure if i'm going to 36's, why not go 38's?
    of course i'd need low gears and all that with the stock drivetrain.

    i'm afraid that if i go to tires that big (even the 36's) that i'm going to break something... and i hate worrying. i would rather over-kill it and never have to worry.
     
  15. cruiserrg

    cruiserrg

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    Ah the how big should I go ? Well I personally always try to build in everything I want at the time. At 36-38 tire size your at a grey area....

    Stock axles with Longfields will hold up to a lot of abuse, but things do break probably inner front axles with a 38. The rear will take this abouse and the weak link will be the pinion, esp on a SOA.

    But over kill would be Dana60 front / 14 bolt rear. But even at 38s you will be draggin a lot of axle around (weight and clearance), shaving would be at the top of my list with a combo like that. It will be very costly, esp considering you want to run at cruiser width.

    Its your choice, stock is good with aftermarket upgrade, but the D60/14bolt offers upgrades in tire size without worries.

    I personally would just stick with stock, add in some aftermarket birfs and 36s or 38s, and be happy until you start breaking every couple trips out. By that time you'll know what tire size and axles you want, and will probably need a new body and drivetrain to go with it.
     
  16. rusmannx

    rusmannx

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    mmmmmm tastes expensive.
     
  17. rusmannx

    rusmannx

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    so uh, if you thought you had connection to any gm axle for good prices (somewhere near free)... what would you go with?
     
  18. dylan

    dylan

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    are you going v8 as well?
     
  19. rusmannx

    rusmannx

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    no, planning on stock engine,trans,tcase.
     
  20. dinkleberry

    dinkleberry

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