Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

12 Bolt Rear Axle Build

Discussion in 'OffRoad Design' started by performance1, Mar 21, 2002.

  1. performance1

    performance1 Registered Member

    Joined:
    Jul 9, 2001
    Posts:
    17
    Likes Received:
    0
    Location:
    Los Angeles. CA
    I have a '89 Blazer (700R, NP241, 350cu, 10bolt-30 spline axles, 33" BFG tires, 4" lift) that I'm planning on replacing the rear axle (and change my gearing from 3.73 to 4.10). My Blazer is used mostly for desert/beach/baja pre-running... very little to no rock use. Never been broken, would like to just upgrade due to mileage (120k) and gearing needs. I do not want the weight, nor need the beef of a 14B! Even though it's going to cost me lots $$, the perfect rear axle for my Blazer would be:
    1. A 12 bolt van axle housing. Provides a 3" wider track than stock; matching the stock front axle housing width.
    2. Convert to Full Floater (Warn FF Kit? Would this work?)
    3. Upgrade axles to heavy duty (ORD? Moser? Warn?)
    4. Convert drum to disc brakes.
    5. Keep my 6 lug rims. NO desire to change to 8 lug.

    Here are my questions:
    1. What year vans offer 12 bolt?
    2. Any 12-bolt van axles with stock disc brakes? If not, approx cost/recommendations on converting to disc brakes?
    (I also need to keep parking brake operational)
    3. If 12B vans only offer 5 and 8 lug, how do I change axles to 6 lug? Is this possible? How? Full Floater Kits available?
    4. Any need to change/adjust my brake proportioning valve?

    It would sure be great if someone made an axle like this. Any help on the above 4 questionswould be greatly appreciated!
     
  2. K10ANDYKHAMNIC

    K10ANDYKHAMNIC 1/2 ton status

    Joined:
    Sep 17, 2001
    Posts:
    1,962
    Likes Received:
    0
    Location:
    Western CO
    u can get the disc brake brackets with the WARN kit . OR i could make some ....
     
  3. jekbrown

    jekbrown I am CK5 Premium Member GMOTM Winner Author

    Joined:
    May 19, 2001
    Posts:
    45,031
    Likes Received:
    366
    Location:
    Vancouver, WA, USA
    with respect to axles, the Warn ff kit comes with their chrome moly axles... no need to upgrade after that.

    J
     
  4. Stephen

    Stephen 1/2 ton status Moderator Vendor

    Joined:
    Sep 15, 2000
    Posts:
    4,227
    Likes Received:
    142
    Location:
    Carbondale Colorado
    You could drop the cash on the 12 bolt, it makes a nice axle. Use the Warn FF kit and you'll probably have to get custom axles for the length. We used Dutchman axles in my old one. The FF kit will make it 6 lug and can be ordered with disc brakes. Truss the housing, add a detroit and you're in pretty good shape. I used a solid pinion shim too.
    Don't have good info on the van housing, my first came from a wrecking yard and then I kind of custom built the second one.

    One option might be a later model SF 14 bolt from an IFS truck. Similar width to the front, 9.5 ring gear, 33 spline axles, 3/4T rated, overall pretty good. And they're 6 lug.
     
  5. K10ANDYKHAMNIC

    K10ANDYKHAMNIC 1/2 ton status

    Joined:
    Sep 17, 2001
    Posts:
    1,962
    Likes Received:
    0
    Location:
    Western CO
    hey umm i have a kinda off topics question about the tubes on the 12 bolt i have , is it "sleeved " over or just larger tubes ?
     
  6. Stephen

    Stephen 1/2 ton status Moderator Vendor

    Joined:
    Sep 15, 2000
    Posts:
    4,227
    Likes Received:
    142
    Location:
    Carbondale Colorado
    there's about 6" of sleeve in each end, the middle is 3.5" .250 wall DOM
     
  7. performance1

    performance1 Registered Member

    Joined:
    Jul 9, 2001
    Posts:
    17
    Likes Received:
    0
    Location:
    Los Angeles. CA
    Stephen,
    Three more questions:
    1. Does your answer to Andy about the sleeves apply to the van axle as you bought it, or was that housing custom built? (other than the additional trussing)
    2. What is the approx cost for a disc brake kit (rotors, calipers, parking brake, etc.) that works with the disc brake brackets you sell as an option with the Warn FF Kit?
    3. Your estimation of custom width axles thru Dutchman is around an extra $150 (is this still accurate?)
     
  8. Stephen

    Stephen 1/2 ton status Moderator Vendor

    Joined:
    Sep 15, 2000
    Posts:
    4,227
    Likes Received:
    142
    Location:
    Carbondale Colorado
    Andy's axle housing was a total custom job. We couldn't find another van housing after I bent the first one so we created our own wide housing. We just used the van dimensions to make it fit the shafts I already had.
    Cost on the disc brake parts can vary a lot so you might do some of your own shopping but I would guesstimate you'll have another $250 or so into calipers rotors and lines. If you go with a parking brake caliper it will be a good bit more. They're the GM IFS 6 lug front rotors and S-10 calipers.

    An extra $150 over the price of the full float kit should be pretty close still. There should be an allowance for the axle shafts in the kit cost but of course when you break a kit and add custom parts it costs more.
     
  9. exblazerowner

    exblazerowner Newbie

    Joined:
    Jan 25, 2004
    Posts:
    2
    Likes Received:
    0
    i have a warn 10/12 bolt full float kit w/disk brake bracket that i bought but never installed (sold blazer). i would like to sell it if you are interested?
     

Share This Page