D20 Parking Brake

Discussion in 'Flat Fender Tech' started by oldtime, Oct 27, 2017.

  1. Oct 27, 2017
    oldtime

    oldtime oldtime

    St. Charles,...
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    Serious considering a flattie build with D20 parking brake.
    Anyone else been there ?

    I don't even have a D20 park brake unit to look at.
    I suppose the park brake sticks up pretty high ???
    Also wonder if my rear propeller length is effected by the brake drum ???

    Planning on a custom transmission floor pan anyway because the D20 will be mated to a T18.
     
  2. Oct 27, 2017
    Focker

    Focker Rust Never Sleeps Staff Member Sponsor

    Tri-Cities WA
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  3. Oct 27, 2017
    jpflat2a

    jpflat2a what's that noise?

    Riverside CA
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    Ken.
    All the part numbers for drum and backing plate are the same as D18
    according to the book.
    You might have that in your hands already.
    I'm trying to picture it all mounted on the rear of the D20 output housing....
    Gotta try and find a picture.
     
  4. Oct 27, 2017
    oldtime

    oldtime oldtime

    St. Charles,...
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    Yeah that's right.
    It's near exacatly the same as a D18 propeller shaft park brake excepting it is mounted onto the D20.

    The D20 or silent type transfer case came out in 1962.
    Apparently the original Jeep D20 rear bearing cap was designed to accept the previously existing 9" propeller shaft brake.
    Like I say I don't have any FSJ books but expect that was original design of the D20 rear bearing cap.
    Looks like the 9" propeller brake became obsolete when AMC began to install the late style 11" Bendix rear brakes in 1972.

    I think these are very good brakes if kept sealed from gear oil.
    They function well with a simple cane lever whereas the late 11" Bendix brakes require increased leverage to activate sufficiently.
    One could even go to a dual parking brake system if they choose.
    Propeller brake plus wheel brake systems.

    My biggest concern with a flat fender application is tunnel clearance.
    But then again I will be doing a custom tunnel to fit D225 and T18 regardless of the transfer case.
    I also plan to measure up and see if the rear propeller shaft length stays constant both with and without the D20 9" drum assembly.
    I have several of the later D20's (post 1971) without the park brake.

    Another thing to think about is that the 9" brake when mounted onto a D20 does not hang down below the case as it does on a D18.
     
    Last edited: Oct 27, 2017
    ITLKSEZ likes this.
  5. Oct 27, 2017
    jpflat2a

    jpflat2a what's that noise?

    Riverside CA
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    Okay.
    The pictures in the parts manuals don't show any accurate mounting photos.
     
  6. Oct 27, 2017
    oldtime

    oldtime oldtime

    St. Charles,...
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    Here's a CL listing with pics ..... Jeep parts
    Note: how the oil fill plug is on the side like all the earlier big hole cases
     
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