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Transmission Information & Noise Guidance

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  • Transmission Information & Noise Guidance

    Original thread link



    Symptom: Noise from transmission, effected by clutch pedal movement.

    Clutch Throw Out Bearing Noise: high-pitched rubbing noise with only slight
    pressure on clutch.

    Pilot Bearing Noise: high-pitched noise when clutch is fully depressed.

    Noise When Clutch Pedal Depressed:
    -throw out bearing, worn, damaged, inadequately lubricated
    -pilot bearing (in flywheel) worn, damaged, inadequately lubricated
    -crankshaft end play should be checked

    Noise When Clutch Pedal Released:
    -Transmission oil level low
    -Misalignment of transmission (more noticeable at low road speed)
    -Clutch disk hub loose
    -Clutch disk springs weak, popped out of cage, or broken
    -Weak or broken return spring on throw out bearing sleeve
    -Sticking throw out bearing sleeve (clean slider, lubricate)
    -Transmission roller bearings worn, damaged, inadequately lubricated
    -Transmission gear damage.

    Other deceiving noises that can “travel” include noise from speedometer cable, starter Bendix, generator bearing/bushing, and water pump bearing.

    Firstly, adjust the clutch for one inch of free play. If noise is eliminated, good.

    Secondly, grease the throwout bearing sleeve. If noise is eliminated, good.

    Thirdly, if noise is still present, the transmission will need to be separated from engine. Best to remove rear end and drive train, unless major engine work is required and, if so, then take it out as a unit with the engine.

    1. This is to diagnose noise coming from transmission and does not address clutch drag/slippage/chattering/pulsating/slippage out-of-gear/lock-up.
    1. The Model A transmission takes three “needle” or roller bearings and two sealed bearings. "Needle"/roller bearings should have their axles poking through their collars, not set into dimples in the collars.
    1. On my two rebuilds I used Bratton’s for parts and cannibalized a decent cluster gear set from an old transmission. Snyders and Berts have received many favorable comments on their transmission parts over the years, also. Buy quality and buy it once. Inspect what you buy for small rust spots (too long on the shelf).
    1. Strongly recommend reading Tom Endy’s articles on the Model A Transmission, found here:
    1. Good pictures of transmission components can be found by purchasing a set of Model A Shop drawings from MAFCA here:
    1. Vince Falter’s FordGarage has an informative, animated video on transmission gear changing created by a VFF member, here:
    1. I discarded my failed needle bearings years ago without taking pictures. One bearing had disintegrated into a handful of rollers with damaged end rings.
    1. Most rebuilders strongly recommend against using STP in a Model A Transmission.
    Last edited by BudP; 02-11-2018, 04:06 PM. Reason: I have been advised by excellent authority that "needle" bearings, while descriptive, are better referred to as roller bearings. The main catalogs describe them as roller bearings or simply

  • #2
    Schwalms cutaway engine / trans!
    2 1930 Tudors

    Henry Ford said
    "It's all nuts and bolts"

    Mitch's Auto Service ctr


    • #3
      Basic parts that should be included in a Trans Rebuild,, By Tom Endy

      Check out Mr. Endys other top notch trans & technical articles.

      2 1930 Tudors

      Henry Ford said
      "It's all nuts and bolts"

      Mitch's Auto Service ctr


      • #4
        Transmission Specifications

        Gear & Shaft Material Chromium alloy steel

        Gear Ratios
        High-1:1 (100%)
        2nd-6.89:1 (53.8%)
        Low-8.75:1 (32.04%)

        Main shaft front (ball) 1208;
        Main shaft rear (ball) 1306

        Transmission Case Length 6.560" to 6.565"

        Case Front Bearing Hole 3.1497" to 3.1507" diameter

        Case Rear Bearing Hole 2.835" to 2.836" diameter
        2 1930 Tudors

        Henry Ford said
        "It's all nuts and bolts"

        Mitch's Auto Service ctr


        • #5
          Clutch Specifications

          Material Molded asbestos composition

          Pressure Plate Weight 15 pounds

          Clutch Disc Weight 2-1/2 pounds

          Pivot Pedal Pressure 30 pounds

          Clutch Facings 9" diameter, 9/64" thick

          Inside Diameter 5-3/4"

          Total Acting Surface Area 75 square inches

          Clutch Pedal Clearance 3/4" for multiple disc, 1" for single

          Clutch Release Bearing Hub 2.065" diameter

          Clutch Throw Out Bearing B7580 or B7580T

          Clutch Pressure 1100 pounds
          2 1930 Tudors

          Henry Ford said
          "It's all nuts and bolts"

          Mitch's Auto Service ctr


          • #6
            2 1930 Tudors

            Henry Ford said
            "It's all nuts and bolts"

            Mitch's Auto Service ctr


            • #7
              I don't think I posted this picture before, and as I recall I took this at the Gilmore Model A museum in Hickory Corners, Michigan. It's in high gear.

              Tranny Cutaway.jpg