Cleaning the Detroit® Automated Transmission Fluid Change and Magnetic Plug

49X mm 26.01.001
    Important: Drain the transmission when the fluid is warm. If not already warm, run the engine until the transmission fluid reaches operating temperature. Shift the transmission to neutral (N) and shut down the engine.

    Notice: Transmission fluid drain intervals are based on many factors, and are specified by the transmission manufacturer. See the details published in the Transmission Fluid Service Information brochure at  to determine oil drain intervals, and use this information to complete the service at the specified mileage.

    Operating a transmission with the fluid level higher or lower than recommended can result in transmission damage. Do not overfill the transmission. Overfilling will force fluid out of the case through the main shaft openings.

    Do not mix types or brands of fluid, because of possible incompatibility. Do not use fluid additives, friction modifiers, or extreme-pressure gear fluids.

  1. Apply the parking brakes, and chock the rear tires. Place a large drain pan under the transmission.
  2. Clean the area around the fill plug, then remove it from the side of the gear case. Remove the drain plug from the bottom of the case. See Fig..

    1. Fill Plug

    2. Drain Plug

    Fig. 1, Drain and Fill Plugs, Detroit Automated Transmissions

  3. Clean the fill plug and the drain plug.
  4. Install a new seal on the drain plug, then install the plug and tighten it 45 lbf·ft (60 N·m).
    5. Notice: Detroit transmissions use synthetic lubricant that meets specific requirements. To see a list of approved lubricants, transmission models, and oil change intervals, see the Transmission Fluid Service Information brochure athttp://dtna.info/DT12FluidsManual.
  5. Add fluid until it is level with the lower edge of the fill opening; see Fig.. See the Detroit Transmission Fluid Service Information brochure at http://dtna.info/DT12FluidsManual, for identifying the transmission type, estimated oil capacities, and applicable oil specifications.

    1. Full

    2. Low

    Fig. 2, Checking Transmission Fluid Level

    6. Note: In all cases, the correct fluid level is established by checking at the fill opening.

  6. Operate the engine for five minutes after filling the transmission, then check the fluid level again.
  7. Install a new seal on the fill plug, then install the plug and tighten it 45 lbf·ft (60 N·m).
  8. Operate the vehicle to check for correct operation.
Note:
Parent topic: Transmission
Document Number: 0000118364
Manual Publication Date: 2024-05-16
Topic Publication Date: 2024-10-31