Understanding the Tractor’s Three Point Hitch System

When buying a tractor, it’s necessary to consider the tasks you want it to handle. Whether it’s an agricultural or industrial tractor, you may need one that can use attachments. And for your tractor to use attachments, it requires a three point hitch.

But what is a three-point hitch for tractor, and how does it work? This article looks into the tractor 3-point hitch to help you understand how to use it effectively in your projects.

What Is a Three-point Hitch?

A tractor 3-point hitch (also called 3-point linkage) is a device that tractor operators use to attach implements to tractors. The design of a 3point hitch is simple, comprising three hydraulic arms joined to resemble a triangle.

The two lower arms (hitch-lifting arms) attach to the front axle. The upper center arm (top link) attaches to the rear axle. Each arm features an attachment device for connecting implements to the attachment holes.

To ensure a secure attachment, operators fit the implement’s posts into the holes and fasten the connections with special pins. The connections at the hitch lifting arms use lift arm pins, while the top link connection uses top link pins.

After lifting the implement, a tractor 3-point hitch adds more weight to your machine. This offers more traction to the tractor while enhancing stability.

You can easily attach or detach the implement without leaving the seat. This reduces fatigue, especially when you’re linking and detaching multiple implements.

A Brief History of the Tractor 3-Point Hitch

The three-point hitch for tractors was developed and popularized by Harry Ferguson in the UK. He made several innovations to the device and called it the Ferguson System. This system comprised the hitch and agricultural implements.

The Ferguson System became a staple device for most farmers in the 1920s. They used it to hitch plows and other farm implements, making their work easier. This system revolutionized agriculture by making tractors versatile while improving safety, traction, and efficiency.

Today, you can use the 3point hitch for tractor with several agricultural and industrial implements. Below are the three point hitch attachments available:

  • Gardening attachments: They include plows, seed planters, cultivators, land levelers, chain harrows, tractor Harley rakes, and subsoilers.
  • Lawn care attachments: They include finishing mowers, sprayers, flail mowers, straw blowers, sickle bar mowers, and PTO fertilizer spreaders.
  • Construction attachments: They include cement mixers, wood chippers, trenchers, 3-point backhoes, tractor post drivers, and scoop pans.

Components of a Three Point Hitch

The tractor 3-point hitch comprises several systems that complement each other. They include the lifting arms, attaching points, hydraulic system, and stabilizers. Below we discuss these systems and their roles.

Lifting Arms

As mentioned earlier, the 3point hitch has two lifting arms (lower arms). They are rigid bars comprising ball joints at each end.

The two lifting arms rely on the hydraulic system to raise or lower implements attached to the tractor. For the lifting arms to move, the operator has to use various settings to control the hydraulic system. These arms connect to the tractor’s front axle to improve stability.

Attaching Points

The attaching points in a tractor 3-point hitch make a triangular formation to provide a secure connection between the tractor and the implement. The two lower attaching points occur at the ends of the lifting arms. They connect the implement to the tractor’s rear axle.

The upper link is a single point that connects the implement to the drawbar. This point is movable but doesn’t rely on the tractor’s hydraulic system.

Another function of the upper link is to sense and actuate the draft control mechanism. Modern 3-point hitch systems have a draft control mechanism. It automatically adjusts the lifting arms when the implement meets resistance, such as roots or stones.

An increase in the draft makes the hydraulic system automatically raise the two lifting arms. On the other hand, when the draft decreases, the hydraulic system lowers the two lifting arms.

Hydraulic System

The tractor’s hydraulic system powers the hitch-lifting arms when raising, lowering, or tilting them. This movement allows one to hook and unhook the attachment. It also comes in handy when operating the entire system, as you can tilt the implement from side to side and raise or lower it.

The hydraulic system in a three-point hitch is dependent on the operator. The tractor features several settings for controlling the hydraulic system.

Stabilizers

The three point hitch for tractors has a stabilizer comprising first and second stabilizer elements. The two stabilizer elements attach to the two lifting arms.

Stabilizers allow the attached implement to remain at the center and avoid swinging sideways. Remember, allowing the implement to sway during operation can foul the tires and increase the risks of accidents.

Before starting any project, inspect the stabilizers accordingly. You’ll also need to check the top link pins and the lifting arms pins to ensure they’re secure.

Categories of a 3-Point Hitch

Three-point hitches are available in different sizes to match the tractor’s strength. Always check the 3-point hitch to understand if the tractor can be used with your implements. Smaller machinery, such as lawn and compact tractors, have tiny 3-point hitches, best suited for smaller implements.

Conversely, larger tractors have bigger and sturdier 3-point hitches for working with larger implements. The best way to select the right category is by measuring pin diameters.

You can also check the spacing between the lower arms. Thankfully, it’s possible to attach a smaller implement to a tractor with a bigger 3-point hitch.

To ensure you buy the right implement for your tractor, here are the 3point hitch categories to consider.

CategoryTractor Horsepower (HP)Diameter of Top Link PinsDiameter of Lift Arm PinsLower Hitch Spacing
0Up to 20 HP16 mm (5/8 inches)16 mm (5/8 inch)510 mm (20 inches)
120-45 HP19 mm (3/4 inches)22 mm (7/8 inch)710 mm (28 inches)
240-100 HP25 mm (1 inch)29 mm (1 inch)860 mm (34 inches)
380-225 HP32 mm (1¼ inches)37 mm (1.4 inches)1,000 mm (40 inches)
4Over 180 HP44 mm (1¾ inches)51 mm (2 inches)1,200 mm (48 inches)

Category 0

This is the smallest 3-point hitch category used on light-duty tractors. You can use this category with lightweight implements on ride-on mowers and compact tractors.

Category 1

Category 1 hitches are available on tractors offering 20-50 horsepower. They’re used in sub-compact tractors and work with Category 1 implements.

You may also find some sub-compact tractors with Limited Category 1 hitch. While Limited Category 1 and regular Category 1 hitches have the same dimensions, their lifting capabilities differ. Limited Category 1 hitch may not lift all Category 1 implements.

Category 2

Category 2 hitches are available on utility tractors offering 40-100 horsepower. They’re sturdier and more heavy-duty than Category 1 hitches.

Many agricultural implements, such as planters and liquid sprayers, can be attached to Category 2 hitches. The good news is you can change the pins or use bushings to connect Category 1 implements to Category 2 hitches.

Category 3

Category 3 hitches are available on large tractors offering 80-225 horsepower. You can attach field and row-crop cultivators to a Category 3 hitch.

When buying this tractor, ensure to differentiate Category 3 hitches from Category 3N hitches. The 3N hitches and Cat. 2 hitches have similar widths. You can apply bushings on Cat. 3N hitches to attach Cat. 1 implements.

Category 4

Category 4 hitches are available in heavy-duty tractors offering over 180 horsepower. It’s the strongest tractor 3-point hitch made of hardened steel to increase durability. Cat. 4 hitch is suitable for large subsoilers and disc harrows.

Note that there’s also a Category 4N hitch with pin diameters similar to a regular Category 4 hitch. However, the lift arm spacing in Category 4N is narrower at 965 mm (38 inches).

How To Adjust a Three-Point Hitch

When connecting or disconnecting implements on your tractor, you’ll need to know how to adjust the 3-point hitch. Adjustment is made at the stabilizers and top link.

The top link is a turnbuckle that you can turn to fine-tune an up or down movement. If you want to lift the device higher, tighten the turnbuckle. If you’re going to lower the device, loosen the turnbuckle.

Adjusting the stabilizers depends on the type of stabilizer your tractor has. You can pull the stabilizers to the desired length to prevent your implement from swinging.

Follow these steps when attaching the implement to your tractor.

  1. Move the tractor towards your implement and ensure it’s aligned with the mounting points. The drawbar should be level with the implement’s top attachment point.
  2. Lower the lifting arms to level them with the implement’s lower attachment points.
  3. Secure the attachment with the lift arm pins.
  4. Attach the drawbar to the implement’s top attachment point and secure the connection with top link pins.
  5. Use the tractor’s hydraulic system to raise the implement off the ground.

Final Thoughts

Hopefully, you now understand a tractor’s three point hitch and how you can apply it in your projects. Remember, it’s necessary to consider the implements you want to use with your tractor. Check your tractor’s 3 point hitch category to know whether it’s compatible with your implements.