In order to understand how to read a transmission data sheet, you must first understand torque. Torque is a torsion force that rotates an object. In automatic transmissions, the torque converter is the force that allows your engine and transmission to run separately.
Deciphering Your Transmission Data Sheet
The Transmission Data Sheet will provide you with vital information about your specific transmission. The data sheet includes physical properties and specifications split into the subcategories:
- Drivetrain Interfaces
- Torque Converter
- Control System
- Physical Description
- Turbine-Driven Power Take-Off Provision
- Oil System
Find out what each section of your Transmission Data Sheet means before you call to order new parts.
The “Ratings” section will tell you how powerful the transmission is. The first four columns are either “Gross Input Torque N•m” or “Gross Input Power kW (hp)”.
The “Gross Input Torque N•m” column is telling you how powerful the torque is in Newton Meters.
The “Gross Input Power kW (hp)” column is telling you the kilowatts exerted from the transmission, and the energy measurement in horsepower is in parentheses.
The drivetrain of a vehicle is what exerts torque power to the driving wheel.
When reading a Transmission Data Sheet, the “Drivetrain Interfaces” section is split into the following rows:
- Acceptable full-load engine governed speed
- Acceptable engine idle speed range (with the transmission in Drive)
- Maximum output shaft speed at 105 km/hr
The engine governor controls the engines speed.
The engine idle speed range lists the appropriate speed while the vehicle is sitting idle in traffic, while the vehicle is still in drive.
An engine’s torque is the amount of force that output shaft can rotate. Therefore, the Maximum output shaft speed at 105 km/hr is measuring the output shaft speed when the vehicle is driving 105 km/hr (~65 mph).
In the columns of the Drivetrain Interfaces section, the appropriate speeds in rpm for each of the above sections are listed.
This section lists the mounting guidelines. The SAE is a measurement system created by the Society of Automotive Engineers to determine the viscosity level of the oil.
By this point, I’m sure you have a basic understanding of a torque converter. In the torque converter section, you’re given the stall torque ratio for each model.
The stall torque ratio is a measurement of the maximum torque application while the vehicle is stalled (the brakes are on).
The control system gives you the specifics of the transmission control module.
Pro Tip: The transmission control helps the engine calculate how and when to change gears for ideal driving performance.
In the “Control System” section, you’ll find the description, shift sequences, driver-to-transmission interface, and the communication protocol.
The physical description gives you the specifics for the SAE listed in the mounting section. The columns are as follows:
- Installation Length
- Dry Weight
The installation length is the approximate length from engine housing to the output flange.
The dry weight is the weight of the vehicle without any oil.
The depth is listed in millimeters with shallow and deep oil slump measurements.
Turbine-Driven Power Take-Off Provision
The power take-off in a vehicle is used to convey the power of the vehicle engine to auxiliary components and the turbine is connected to an input shaft. The power take-off also generates a speed signal interpreting the transmission turbine speed. In this section of the Transmission Data Sheet, you can read the specific equipment needed for the power take-off.
In this section of the Transmission Data Sheet, you will find the oil system appropriate for your transmission. The approved liquids will be listed along with the liters for a deep and a shallow oil pan.
Transmission Data Sheet Application
Deciphering through a Transmission Data Sheet can be difficult at times. However, data sheets are essential for the installation and application of transmissions. You can browse Copeland Allison Transmissions and view the transmission data sheet for specifications.
Contact Us to learn more about which rebuilt transmission is right for your application whether Material Handling, Foundational Drilling or Mining and Construction Applications. You can refer to the data sheet when calling to schedule service for your transmission.