1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

11" Rear Drum Brake Upgrade Questions

Discussion in 'Early CJ5 and CJ6 Tech' started by Vanguard, May 8, 2008.

  1. Vanguard

    Vanguard Take Off! Staff Member

    Okay. Last night my four year old and I beat Betsy into submission and managed to remove the driver's rear side rear hub. This was necessary after I used my superior Conan-like strength to break another bleeder screw and of course the easy out I used to attempt extraction as well. :D

    So instead of replacing another 9" wheel cylinder I decided to upgrade my rears to 11". I've had a used set brales for some time, but I just noticed that they seem to be front backing plates rather than rears. I understand that they should be similar however rear backing plates are supposed to have provisions for parking brake cables. If I use these should I use wheel cylinders, hardware and shoes designed for the front or should (can) I use the wheel cylinders, hardware and shoes for the rear?
     
    Vanguard, May 8, 2008
    #1
  2. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    You have 11" on the front? You need the rear cylinders, otherwise the braking force will not be correctly proportioned. AFAIK all the hardware is the same, front and rear, except for the added/missing PB equalizer bar, spring and lever.
     
    timgr, May 8, 2008
    #2
  3. EricM

    EricM Active Member

    Do you have 11 inch brakes on the front? I'm sure someone smarter than me will chime in, but you probably want to check the diameters of the wheel cylinders. I believe the wheel cylinder diameter of the front brakes is larger than the rear brakes. This is one way to proportion them without a proportioning valve. Whatever you do, you probably want the wheel cylinder diameter of the front brakes to be larger than the wheel cylinder diameter of your rear brakes.

    ETA: looks like Tim beat me to it.
     
    EricM, May 8, 2008
    #3
  4. Vanguard

    Vanguard Take Off! Staff Member

    Yep. I have 11" brakes on the front already. After further research it looks like the hardware part numbers are the same and the shoes are the same. So I'll use the rear wheelcylinders with new hardware, new shoes and the old star adjusters.
     
    Last edited: May 8, 2008
    Vanguard, May 8, 2008
    #4
  5. 66cj5

    66cj5 Jeep with no name

    i would replace the star adjuster since your're changing everything else.
     
    66cj5, May 9, 2008
    #5
  6. Vanguard

    Vanguard Take Off! Staff Member

    The adjuster's are $14 a piece. The old ones are in good shape. I'm replacing the springs since I don't know their age and their jeep ($7 covers both sides).
     
    Vanguard, May 9, 2008
    #6
  7. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    The hardware kit should include springs, nails, cup washers, adjuster cable, cable guide, maybe the adjuster lever (EIS includes it). Make sure you have the little washer between the cup and the screw on the adjuster. I put a dab of white grease on all the bearing surfaces, in particular on the little plateaus on the backing plates. If you clean up the adjuster and lube it well, it should be fine as long as it's not corroded. I always clean the threads on the adjuster screw with the wire brush on the grinder, then thinly coat the threads completely with white grease.

    You can test the return springs. Drop them on a concrete floor. If they buzz, they are finished. Good ones will make a click, like a pebble.

    I've done a few of these :)
     
    Last edited: May 9, 2008
    timgr, May 9, 2008
    #7
  8. Vanguard

    Vanguard Take Off! Staff Member

    I think the kit includes the springs, nails and cup washers. I'm pretty sure it didn't contain the cable or cable guide.

    I will definitely take care of the threads and grease.

    I hope to have it completed this weekend. :D
     
    Vanguard, May 9, 2008
    #8
  9. Vanguard

    Vanguard Take Off! Staff Member

    That was a good call Karl! The old ones looked good but were frozen. Picking up a couple in the morning. :beer:
     
    Vanguard, May 10, 2008
    #9
  10. michigan_pinstripes

    michigan_pinstripes I'm not lost, I'm wandering

    Hmm, maybe I will attack rear brakes today.

    11" misc parts available at the Zone under "mail Jeep?"
     
    michigan_pinstripes, May 11, 2008
    #10
  11. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    '72-75 CJ will work.
     
    timgr, May 11, 2008
    #11
  12. Vanguard

    Vanguard Take Off! Staff Member

    Yep. All the parts I've used were for a '74 CJ5.
     
    Vanguard, May 11, 2008
    #12
  13. tommy b

    tommy b Member

    The parts I used were from a 72 Waggy. See tech library article, "Early CJ Drilled 11" brake Swap" for vehicles whose parts will fit.

    tommy b
     
    tommy b, May 13, 2008
    #13