Comparing Tractor Engines: Which Type is Right for You?

There’s plenty to consider when you’re shopping for a tractor based on the type of work you’ll be doing and the land you’ll be working on. That’s why it’s important to pay attention to the type of engine a tractor has for your day-to-day operations. For a quick lesson on the different types and sizes of tractor engines, here is some guidance to help you make a confident purchasing decision. 

Types of Tractor Engines by Fuel

Tractor engines burn different types of fuel that affect an engine’s performance. 

Gas Engines

Once the most common type of engine in tractors, gas-powered models are less popular now. Gas engines are lighter than diesel engines and offer less torque and power. You can still find gas engines in older models of compact tractors, which tend to be less expensive with upfront costs and maintenance expenses. 

Diesel Engines

Diesel engines are most common for tractors. These internal combustion machines use compression ignition instead of spark plugs to burn fuel. Diesel engines deliver higher torque at lower speeds, which is best for plowing and towing heavy loads with a tractor. They are also more fuel efficient and durable than gas-powered engines. 

Hybrid Engines

Hybrid tractors utilize an internal combustion engine similar to diesel but with an electric motor. This results in a more fuel-efficient tractor, with lower emissions, that still delivers dependable performance. 

Biofuel Engines

As the equipment industry looks for more sustainable options, more types of electric equipment and machines that use biofuel are entering the marketplace. Biofuel engines are powered by alternative fuels such as biodiesel, E98 ethanol, biomethane, and vegetable oil, which are beneficial for reducing carbon emissions. Biofuel engines can also run on a combination of conventional diesel and biodiesel. Earlier this year, John Deere revealed plans for an E98 ethanol-powered tractor prototype at Commodity Classic 2026. 

Types of Engine Cylinders

In addition to fuel type, tractor engines can be classified by the number of cylinders. The configuration of an engine’s cylinder affects the tractor’s power, operating smoothness, vibration, and fuel efficiency. 

Single-Cylinder and Two-Cylinder Engines

A single-cylinder engine uses one piston to generate power. Single-cylinder engine tractors tend to be smaller lawn machines or vintage tractors, like the historic Lanz Bulldog. Similarly, two-cylinder engines are typically used in vintage agricultural equipment. While these lower-cylinder tractors are less expensive and easier to repair (outside of vintage models), they aren’t ideal for large acreages since they offer less power and efficiency than machines with more cylinders. 

Multi-Cylinder Engines

Multi-cylinder tractor engines can range from three to six cylinders. The more cylinders an engine has, the more smooth, consistent power it can produce. This steady power makes a huge difference, especially when utilizing tractor attachments. 

Three-cylinder engines are commonly found in compact tractors, like the Kubota B01 Series, and are good for light-duty farm work. Four-cylinder engines and higher are best for tough jobs and long hours, and they’re most common in powerful mid- and full-size tractors.  

Heavy-duty tractors use a six-cylinder engine that delivers raw power and high torque for the toughest jobs. John Deere produces a six-cylinder, 18-liter diesel engine for the brand’s industrial 9RX series, while the Claas Axion series features six-cylinder diesel engines as well. 

Types of Engine Strokes

Another classification for tractor engines is by stroke. This refers to the distance the piston travels inside the cylinder. The longer the stroke, the more torque and power the engine delivers. Keep in mind, this also uses more fuel. 

Two-Stroke Engine 

A two-stroke engine, also known as single stroke, is best equipped for smaller engines. While most modern manufacturers no longer produce two-stroke engines, you can find them in smaller, vintage tractors. These were phased out by tractor brands because two-stroke engines burn oil with fuel, which led to increased emissions. 

Four-Stroke Engine

A four-stroke, or dual-stroke, engine completes one power cycle in four piston movements to provide longer output, smoother idling, and higher torque. Four-stroke engines are utilized in almost all modern-day tractors, including top manufacturers like John Deere. 

Understanding a tractor’s engine is about more than just horsepower. As you can see, the size of an engine, fuel efficiency, torque, and maintenance needs—including what’s involved with engine rebuilds and repairs—all affect the overall performance of a machine. Knowing more about the different types and sizes of engines while you shop for a tractor can help you find the right model for your work.