The Different Types of PTO Shafts

The Different Types of PTO Shafts

Without the PTO, a tractor cannot drive to complete its most basic of functions. Comprehending the different types of PTO shafts, parts, and their respective uses will allow for better practice with farm machinery. After all, you want an investment in expensive and necessary equipment to last as long as possible.

How Does It Work?

The Power Take-Off shaft transfers power from your tractor to the equipment of your choice. The PTO driveline is where everything that needs power on a tractor derives its power from. PTO drivelines are often overlooked during routine maintenance checks but should not be ignored as they are crucial in operating farm equipment.

Size Importance

Regardless of what job you’ll be using a PTO shaft to complete, it’s important that you have the right size. The manufacturer should provide length recommendations to help you get an idea. When measuring a PTO shaft, use a tape measure and measure from the outside of each yoke to obtain the closed length. The series size should correspond with the amount of horsepower your tractor has. There are two different speeds used most commonly with tractor PTO shafts, the 540 (type 1) and 1000 (type 3) RPM.

Parts of PTO Shaft

It’s essential that you understand sizes, measuring, horsepower, and agriculture PTO shaft parts to choose the proper PTO shaft for your farm machinery. Though the yokes and U-joints are necessary for function, the safety chains and shield are very important parts of the PTO shaft to keep you safe during use.

  • Internal Yoke- There are two, located at both ends of PTO shaft -tractor and implement. This is welded to the drive end.
  • Universal Joint- There are two, located at both ends of PTO shaft.
  • External Yoke- There are two, located at both ends of PTO shaft. It has a “Y” shape to connect to the U-joint and a female hole.
  • Safety Chains- The chains are used to secure the PTO shaft onto the equipment and onto the tractor.
  • Safety Shield- These cones are found on both ends.

Two Main Shaft Types

To identify the type, you’ll need to look at the shape of the shaft. Regardless of the type, the front is the same as the secondary shaft. However, the front shaft is larger to allow the secondary shaft to fit inside. This way the pieces can collapse like a telescope during movement.

  • Domestic- shaped shafts would be one of four shapes- round, rectangle, square, or splined.
  • Metric- shaped shafts would be a star, bell, or football shape.

Three Main Types Of PTO

The type of PTO you choose definitely depends on the job you need to do. If you’re plowing, mowing, or shredding, there is a Power Take-Off shaft that is best for each task and helps guard your machinery against unnecessary pressure, hits, or tension.


This is designed for equipment that is not projected to meet any sudden halts. It’s a yoke-to-yoke arrangement. This can be used for large mowers, as the movements will be smooth and there shouldn’t be times of resistance or stopping.

Shear Pin

Can be used with equipment such as a chipper. The end yoke is in two pieces and uses a shear pin to hold them together for operation. The pin absorbs the shock if there is a sudden stop to avoid damaging the driveline.

Slip Clutch

Slip Clutch is designed to protect your tractor and your attached equipment from being damaged by internally sliding- allowing movement when an object is struck. For example, as the seasons change, rocks and stones come to the surface, and when you hit them, you want the shock absorbed so you don’t cause damage to the gearbox.

Possible Problems

Due to PTO shafts being used for agricultural equipment that experiences high stress and loads when operating, failure can occur. Paying attention to where the issue is happening will help you identify the cause of the problem.

Compression Issues

Constant compression of the PTO shaft for an extended period of time can result in damaged connections on the PTO, connecting shafts, implement, tractor, or bearings. Any of these occurrences can be fixed by shortening the PTO shaft length. Turn to the experienced professionals at DriveShaft of Tulsa to do this correctly and in a timely manner to get you back on track to completing your tasks quickly.

Wear and Tear

When you’re operating agricultural equipment, there’s inevitably going to be wear and tear. Areas to watch out for this especially are with the yoke ears or sides that can be damaged from working excessively at angles. If the angle exceeds forty-five degrees, the PTO should be disengaged.

Telescoping tubing and sections can also experience excessive wear if lubrication is lacking where the tubes overlap. Insufficient lubrication can also cause undue wear on shield bearings. Without proper lubrication, the friction between these bearings is too great. They should be lubricated every eight hours.

Damaged or Broken Parts

It’s important to pay attention when things start to run less smoothly, or you find your attention on an area of the machinery that ordinarily runs smoothly. Damage to parts can happen anywhere from telescope tubes to cross-bearing arms, or joints to yokes. Be aware of the shock load on your equipment and make sure that you are using the right type of PTO for the job you are attempting to accomplish. Heavy-duty equipment can take a lot of stress, but it’s important to stop if something isn’t right before damaging beyond a simple fix.

Clutch Issues

The majority of Power Take-Off shaft failures and issues stem from an improperly adjusted clutch or the complete absence of one. If you are planning to rotate farmland or implement jobs of continuous contact, be sure that you are using a slip clutch to absorb the strikes.

There is a lot of information regarding the different types of PTO shafts. You don’t have to be an expert on the complete innerworkings of these shafts; however, you do need to have a basic understanding in order to protect your heavy-duty agricultural equipment and make it last. When something isn’t quite right with your driveline and PTO shaft, it’s best to consult the experts at DriveShaft of Tulsa do avoid doing further damage to the machinery and protect your investment.

The Different Types of PTO Shafts