29546210 | Genuine Allison® Push Button Shift Selector

1. Simplifies Gear Shifting

Instead of using a bulky gear lever, the driver just presses buttons labeled:
D (Drive)
N (Neutral)
R (Reverse)
Sometimes M (Manual), ↑ / ↓ (gear up/down), or Mode
This eliminates manual shifting and makes operation easier—especially for inexperienced drivers or in high-turnover fleets like buses or delivery trucks.

2. Saves Space in the Cab

No shift lever means more legroom and better dashboard design
Easier to move between seats in buses, RVs, or emergency vehicles
Especially helpful in vehicles with tight cabs or need for walk-through access

3. Integrates with Electronic Transmissions

Push button selectors:
Communicate directly with the Transmission Control Module (TCM)
Allow for diagnostics, programmable modes, shift scheduling, and fail-safes
Support CAN bus or proprietary data protocols in modern vehicles

4. Enhances Safety

Prevents accidental shifts (e.g., can't shift into reverse while moving forward)
Built-in lockouts, fail-safes, and indicators
Can be programmed to default to Neutral on engine shutoff

5. Improves Vehicle Ergonomics & Aesthetics

Cleaner dashboard appearance
Easier for OEMs to design around it
Can include LED display for active gear, fault codes, or shift messages

6. Reduces Wear & Tear

No mechanical linkages = less maintenance
Less chance of driver abuse or mis-shifting
Improves transmission life by using precise electronic commands

• Doesn’t respond when buttons are pressed

• Wrong gear selected or flashing gear indicator

• Display screen malfunctioning

• Communication fault with TCM (codes present)

• Vehicle stuck in one gear (often “limp” or “neutral”)