Your Guide to Power Take-Offs

Power take-offs (PTOs)—often spelled “power takeoffs”—are used in various mechanical systems to serve as a bridge that channels power from a primary engine to auxiliary equipment. Primarily recognised for their extensive use in hydraulic applications, PTOs harness the engine power of a vehicle, such as a truck, to operate machinery ranging from hydraulic pumps to air compressors.

While often associated with commercial vehicles, their versatility also extends to agricultural machinery, enabling operations like running a water pump. Let’s explore PTOs in more detail.

What Is a Power Take-Off (PTO)?

A power take-off is a mechanical device that is primarily used to transfer power from the engine of a vehicle or machinery to auxiliary equipment or secondary systems. It works by connecting directly to the power source of the vehicle (usually the engine or transmission) and harnesses that energy to operate external attachments or implements. This allows the PTO to convert engine power into usable energy that can drive equipment like hydraulic pumps and other types of gear.

In other words, a PTO captures the existing power generated by the vehicle’s engine and redirects it for other tasks. That makes PTOs a vital part of standard operations in various industries, including agriculture, construction, and emergency services, where they enable heavy machinery and vehicles to perform a range of useful roles beyond just transportation.

The mechanics of a PTO involve a splined output shaft that connects to the drive shaft of the auxiliary equipment. The connection allows the rotational power of the engine to be transferred to another device. PTOs can be engaged and disengaged as needed, offering control over when and how much power is diverted from the engine. This selective engagement is extremely useful for equipment that does not need to run continuously, such as a winch on a tow truck or a hydraulic lift.

What Are the Different Types of PTOs?

Power take-offs come in various designs, each suited to different vehicle configurations and operational needs. The most common types of PTOs include:

• Transmission Mounted PTOs - These are mounted directly to the truck transmissions and can be operated with the vehicle in motion or in stationary position. This type of PTO is highly versatile and is commonly used to operate hydraulic pumps, air compressors, and other devices that require substantial amounts of power.
• Engine Mounted PTOs - Engine mounted PTOs are connected directly to the engine and can provide power even when the vehicle is stationary, so they’re ideal for applications that require constant hydraulic flow, such as refrigeration units or cement mixers. They tap directly into the engine power before it reaches the transmission.
• Sandwich Split Shaft PTOs - This type involves installing a second engine transmission between the main engine and the vehicle transmission. It is called "sandwich" because it splits the power between the primary transmission and additional equipment. This type of PTO can handle high-power demands and is typically used in fire trucks and similar vehicles where multiple types of heavy equipment operate simultaneously.
• Side Mount PTOs - These are attached to the side of a vehicle’s transmission and are particularly useful in applications with space constraints. Side mount PTOs are less common but are vital in certain setups where other types of PTOs would not fit.

Each type of PTO has its own set of strengths and limitations. Transmission mounted PTOs offer ease of integration and control, making them a go-to choice for many industries. Engine mounted PTOs provide continuous operation capability that is essential for applications like mixing concrete. Sandwich split shaft PTOs offer power for complex operations, especially in emergency and utility services. Finally, side mount PTOs offer solutions for tight spaces and specific vehicle configurations.

How to Choose the Right PTO for You

Selecting the right power take-off is essential for ensuring that your machinery operates efficiently and meets the demands of your specific applications. We have some tips to help you choose the best PTO for your needs:

Assess the Power Requirements

Start by determining the power requirements of the auxiliary equipment you plan to operate. Different types of PTOs offer varying levels of power output, so it’s essential to match the PTO’s capabilities with the hydraulic pump or other devices’ power needs. Consider the horsepower and torque requirements and ensure the PTO can meet or exceed these specifications.

Understand the Vehicle Specifications

Not all PTOs fit all vehicles. You must understand the specifications of your vehicle, especially the type of transmission and the available space for PTO installation. Check if your vehicle's transmission is compatible with a transmission mounted PTO, or if space constraints require a side mount PTO.Consider the Application

The type of application greatly influences the type of PTO required. One major factor is whether it will be operating on an intermittent (under five minutes at a time, and only a few times per day) or continuous basis. Also, consider the environment in which the vehicle operates. For example, construction and forestry environments might have different requirements compared to agricultural applications.

Evaluate Engagement Options

How the PTO is engaged—whether manually or automatically—can impact usability and efficiency. Some PTOs offer hydraulic, pneumatic, or electric shift options, which provide different benefits in terms of ease of use and control.
Taking these factors into account will improve your chances of finding a PTO that really works for your needs.

Contact White House Products Today

If you’re not certain about the right type of PTO, you can always contact White House Products for insights into the best model for your specific vehicle and application. We’re proud to offer the finest hydraulic parts and accessories available online. Feel free to contact us at +44 (0) 1475 742500.