Detroit® Model 4 and Model 6

49X mm 35.01.001

Notice: When operating under adverse conditions, it may be necessary to change the axle lubricant at more frequent intervals than listed in the scheduled maintenance tables. Failure to do so could result in axle damage.

For all axles, including tandem drive axles and two-speed axles, perform the applicable procedures under the heading, ‘All Axle Models.’ For a two-speed axle with a shift unit, also change the shift unit lubricant; see under the heading, ‘Two-Speed Axles With Shift Unit.’

  1. Park the vehicle on a level surface, shut down the engine, and set the parking brake. Chock the tires.
  2. Clean the fill plug and the area around it. In the axle housing rear cover, remove the plug from the oil fill hole. See Fig..

    • Front View

    • Rear View

    1. Axle Breather

    2. Breather Hose

    3. Temperature Sensor Port

    4. Oil Fill Plug

    Fig. 1, Detroit Model 4 and Model 6 Tandem Axle (forward axle shown)

    3. Caution: Be careful when draining the axle oil. It may be very hot, and could cause personal injury if it contacts the skin.

  3. Place a drain pan under the rear axle drain plug. Drain the oil when it is warm. At this temperature, the oil will run more freely and ensure that the axle is flushed.
  4. Clean the fill and drain plugs. Change them if necessary.
    1. For magnetic plugs, use a piece of key stock or any other convenient steel slug to short the two magnetic poles and divert the magnetic field.
    2. Clean away the collected material deposited on each pole. Magnets will rapidly lose their effectiveness as collected material bridges the gap between the two poles.
    3. After the first oil is changed, inspect the drain plug each time for large quantities of metal particles.
    4. After cleaning, install the drain plug(s) and tighten to 30 lbf·ft (41 N·m).
  5. Fill the axle with the recommended lubricant. See Table.for recommended drive axle lubricants and Table. for lubricant capacities.
    1. Fill the axle through the oil fill hole. Lubricant should be level with the bottom of the oil fill hole. To check fluid level, see Fig..

      • Correct (lube level at bottom of fill hole)

      • Incorrect (lube level below fill hole)

      Fig. 2,  Axle Lubricant Level Inspection

    2. Install and tighten the fill plug 30 lbf·ft (41 N·m).

      Table 1, Detroit Drive Axle Lubricants, Model 4 and Model 6

      Detroit Drive Axle Lubricant, Model 4 and Model 61
      Lubricant Type Ambient Temperature

      Mobil Delvac 1 Gear Oil 75W-90

      Synthetic

      –40°F (–40°C) and up

      2

      IMPORTANT: Lubricant used in Detroit rear axles must meet Mercedes-Benz specification 235.8/Detroit Fluids Specification (DFS) 93K219.01. Mobil Delvac 1 Gear Oil 75W-90 meets this specification. For more product information, see http://bevo.mercedes-benz.com or https://ddcsn-ddc.freightliner.com/cps/rde/xchg/ddcsn/hs/5931.htm
      1. Detroit rear axles do not require the use of friction modifiers.
      2. There is no upper limit on the ambient temperature.

      Table 1, Detroit Drive Axle Lubricants, Model 4 and Model 6

      Table 2, Detroit Rear Axle Lubricant Capacity, Model 4 and Model 6

      Detroit Rear Axle Lubricant Capacity, Model 4 and Model 6 (Hubs Full)
      Axle Oil Capacity: Quarts (liters)

      Forward-Rear, Model 4

      14.3 (13.5)

      1

      Single and Rearmost Tandem, Model 4

      10.6 (10.0)2
      1. These values assume the wheel ends are properly lubricated. Actual oil capacity might vary slightly depending on gear ratio.
      2. These values assume the wheel ends are properly lubricated. Actual oil capacity might vary slightly depending on gear ratio

      Table 2, Detroit Rear Axle Lubricant Capacity, Model 4 and Model 6

Note:
Parent topic: Axle Lubricant and Filter Change, and Magnetic Strainer Cleaning
Document Number: 0000119473
Manual Publication Date: 2024-05-16
Topic Publication Date: 2024-10-31