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Finned Or Smooth Drums

Discussion in 'Early CJ5 and CJ6 Tech' started by a-fisherman, Jan 10, 2025.

  1. Jan 10, 2025
    a-fisherman

    a-fisherman New Member

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    I have a 1968 Cj-5 and I am updating to 11" brakes. I acquired a set of backing plates brakes and drums from a 1973 Cj. The drums are smooth, but my mechanic wants me to order kits from the jeepsterman and the drums look to be the finned type. I am using 15inch wheels from Discount tire that I purchased many years ago. Will the finned drums work, or should I stay with the smooth drums? THX-Derral--
     
  2. Jan 10, 2025
    oldtime

    oldtime oldtime

    St. Charles,...
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    Just depends on the wheel shape,
    I would expect that most all 15” aftermarket wheels should work well with 11” finned drums.
     
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  3. Jan 10, 2025
    Ol Fogie

    Ol Fogie 74 cj5 304, 1943 mb

    Southern...
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    X2, the factory 6.5 inch x 15 in wheels will work fine with the finned drums too. My 74 came with them.

    The older K&H steel 8 inch factory renegade wheels will only work with the smooth 11 inch drums. By the time the 74 year model cj5 came out with the finned drums, the renegades wheels were the cast aluminum slotted wheels.
     
  4. Jan 13, 2025
    a-fisherman

    a-fisherman New Member

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    There is one more challenge on my brake conversion. The backing plates are set up with e-brakes on the rear drums. Has anyone converted the OEM e-brake on the transfer case to the type on the rear brakes? If so, what is used to accurate the brakes and what other items are required? THX--Derral--
     
  5. Jan 13, 2025
    Fresbone

    Fresbone Member 2025 Sponsor 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Fresno, California
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    I am in the process of doing that. I would set it up like a 69 C101. You will need to fab some brackets, but the cables should be available and you can get a used cane from a place like Partsdude.
     
  6. Jan 14, 2025
    Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

    Tantallon, Nova...
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    It's been discussed before, try a search.
     
  7. Jan 14, 2025
    colojeepguy

    colojeepguy Colorado Springs

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    Jeepster cable would be too long for a CJ5
     
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  8. Jan 14, 2025
    jeepdaddy2000

    jeepdaddy2000 Active Member

    Eagle Point oregon
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    Finned drums were designed to help dissipate heat, IMHO, really not an issue with most CJ's.
    If that is what you are looking for, google "drilling drums", which also helps with water drainage. This was a fad back in the 80's and 90's that grew out of the hot rod scene.
    http://www.earlycj5.com/xf_cj5/index.php?threads/121127/
     
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  9. Jan 14, 2025
    Oldpappy

    Oldpappy A.C. Fults - Curmudgeon at large 2022 Sponsor

    East Tennessee
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    The 15" wheels on my CJ5 would not clear 11" drums, smooth or finned and I had to use spacers. I don't know what brand of wheels these are. I also did an 11" conversion on a CJ2A and it has KH 16" wheels. These barely clear the smooth 11" drums used on that Jeep.

    So, it all depends on what kind of wheels you are using, but with standard CJ steel wheels I would suggest going with the smooth drums.

    Having rear backing plates that facilitate parking brakes affords an option of splitting the two brakes to separate floor leavers to allow braking the rear wheels individually. Some call this "cutting brakes", as it can aid in tight turns, but I have used this as a traction aid. If you don't have a locker or LS rear end, this is a good alternative.
     
    Ol Fogie likes this.
  10. Jan 14, 2025
    colojeepguy

    colojeepguy Colorado Springs

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    I tried this on my Jeep, hoping it would help with creek crossing. It didn't.
     
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