Axial Mounted Brakes

sb mm 42.20.003

    Important: The following information applies to all types of axial mounted brake applications.

  1. Park the vehicle on a level surface, shut down the engine, and set the parking brake. Chock the tires.
  2. Raise the vehicle and support it on jack stands.
  3. Using a tire runout gauge, check the radial runout. Write down the measurement for later use to avoid vibration complaints. For instructions see General Information, Wheels and Tires in the Shuttle Bus Chassis Workshop Manual .
  4. Mark the two studs closest to the valve stem for proper wheel assembly location when reinstalling the wheel assembly on the hub.
  5. Remove the wheel assembly.
  6. Note: In all steps that require a torque wrench, use a Snap On torque wrench ATECH4RS600, or an equivalent, with a center to handle length of 47 inches (119 cm).

  7. Set a torque wrench to 350 lbf·ft (475 N·m) and tighten the caliper mounting bolts following the tightening pattern shown in Fig.. If they do not turn, no further work is needed. If they turn, take the vehicle to an authorized Freightliner dealer to have all of the caliper bolts on that wheel end replaced. Due to limited caliper bolt access, it may be necessary to use tool DDC DSNCHA018005 referenced in tool letter 18TL18. If the tool is needed, use tool DDC DSNCHA018005 only and no other tools. See Fig.. If the tool is needed, see Table. for torque specifications for a 47 in (119 cm) long wrench.

    Fig. 1, Axial Bolt Tightening Pattern

    Fig. 2, DDC DSNCHA018005 30mm Air Disc Brake Caliper Brake Bolt Torque Adaptor

    Table 1, Torque Check with 47 Inch (119 cm) Torque Wrench and Tool DDC DSNCHA018005

    Torque Check with 47 Inch (119 cm) Torque Wrench and Tool DDC DSNCHA018005

    Angle View

    Extension Angle (degrees)

    Target Torque ~~*~lbf·ft (N·m)]

    Tool Setting ~~*~lbf·ft (N·m)]

    0

    350 (475)

    296 (401)

    45

    310 (420)

    60

    320 (434)

    90

    350 (475)

    120

    386 (523)

    135

    402 (545)

      Table 1, Torque Check with 47 Inch (119 cm) Torque Wrench and Tool DDC DSNCHA018005

    1. Using the two studs marked earlier as a guide, install the wheel assembly. When correctly installed, a line drawn from the valve stem through the center of the wheel assembly should go between the two marked studs.
    2. Using a tire runout gauge, measure and record the radial runout of the tire and wheel assembly. The measurement should be as good or better than the measurement recorded earlier. For instructions see General Information, Wheels and Tires in the Shuttle Bus Chassis Workshop Manual .
    3. Perform the steps above for each wheel location until all wheel locations have been inspected.
    4. When all wheel locations have been inspected, remove the jack stands and lower the vehicle.
    Note:
    Document Number: 0000120820
    Manual Publication Date: 2025-01-08
    Topic Publication Date: 2024-11-18