Manual Mode (M)

P4 DM Ch17; CasGen5 DM Ch15

Refer to the Allison website for additional information: see www.allisontransmission.com.

In manual mode, the driver selects the maximum allowed range. This may be helpful when traversing a work site, railroad tracks, or steep grades, for example.

When in automatic mode and with the D/N/R switch set to drive (D), a long push on the shift control mode switch activates the manual mode (M). To increase selected range, pull the lever up (towards you); to decrease the selected range, push the lever down (away from you). The transmission will not upshift above the selected range unless the hold override upshift speed is exceeded.

See Fig. for an example of the driver display with the transmission in manual mode.

  1. Current Gear

  2. Selected Gear

Fig. 1, Allison Gear Display in Manual Mode

Note: The transmission may deny a downshift if the engine speed would fall outside of the acceptable range.

Note: If attempting to select a non-Neutral mode without applying the service brakes, the transmission will not shift into gear. To shift into gear, select Neutral (N), apply the service brakes, and select the desired mode again.

Note:
Parent topic: Allison Automatic Transmissions
Document Number: 0000111585
Manual Publication Date: 2024-09-03
Topic Publication Date: 2025-03-07