Allison Transmission Control Module (TCM) – Part No. 63CR0331

This unit is a high-performance Transmission Control Module (TCM) manufactured by Allison Transmission. It serves as the primary electronic brain for managing gear shifts, torque converter engagement, and diagnostic functions for heavy-duty automatic transmissions.

Technical Details & Compatibility

• Series: Part of the Allison A63 generation of controls.
• System Voltage: Compatible with both 12V and 24V electrical architectures.
• Application: Commonly used in heavy-duty vehicles equipped with 4500SP or similar vocational series transmissions.
• National Stock Number (NSN): 2520-01-677-2591.

⚠️ Please Note:

This module is a software-dependent component. Because TCMs are typically calibrated to a specific vehicle's engine torque curves and axle ratios, a replacement unit may require reprogramming or "flashing" with the correct software calibration before it will function correctly in your vehicle.