Nowadays, you cannot imagine a tractor without PTO.
Of course, you may come across farm machinery that may not have the PTO shafts, but it’s rare.
A tractor can not drive and complete the essential operations and functions without a PTO.
In addition, other agricultural equipment also can not operate without the tractor PTO.
So, what is a tractor PTO, and why are the PTO driveline parts so important?
Please look at our comprehensive guide below, and find all the essential information regarding the tractor PTO parts.
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What is a tractor PTO?
The tractor PTO stands for Power Take-off.
It’s a tractor PTO shaft that transfers the energy from the tractor to the attached agricultural equipment and implements.
The tractor PTO driveline is a system that ensures all components and attachments requiring a tractor power derive the power from.
However, the PTO driveline is often overlooked during maintenance, but you must not ignore them; they are critical for the optimal performance of your agricultural machinery and farm equipment.
As a tractor is a high-torque vehicle, a multitasker for numerous agricultural tasks, it is mainly used for pulling different implement models; the tractor PTO is obligatory.
So, the tractor can move equipment and machinery necessary for spraying, pumping water, threshing, rotavator, etc.
Of course, you can encounter the tractor PTO mounted on the rear side and the front side of the tractor for front equipment and attachments.
The history of tractor PTO
The first PTO tractor was presented by the Internal Harvester Company in 1918, with its 8-16 models.
The company’s engineer Edward A. Johnson came up with the idea of the tractor PTO shafts first.
Once he created the first tractor PTO shafts, his team conducted various tests to determine the validity of the PTO shafts, their important parts, and potential issues with the items.
However, with time, the PTO shafts were commonly seen in various tractor brands, too. And by 1920, the IHC presented their 25-30 tractor models tested in Nebraska.
The tractors were also successful for the PTO shaft parts and their validity.
How does the PTO work?
The tractor PTO shafts are created to generate and direct the engine power to the attachments and convert it into the engine rotation to hydraulic.
So, if the tractor PTO shafts use fluids in energy, then the mechanism is called hydraulics.
Thus, you can effortlessly move various implement types and other components with less power. In other words, the tractor can not perform without the PTO shafts.
Main types of the PTO activation methods
There are two main types of PTO activation:
- lever type
- switch type
Therefore, the tractor PTO is operated via the primary transition clutch or a remote control mechanism acting on the very PTO.
Hence, an air valve is applied to engage the PTO; however, you have other options, such as:
- mechanical linkage
- electric mechanism
- hydraulic mechanism.
A mechanical power take-off refers to automatic gearboxes attached to truck transmissions, used to transfer the vehicle engine’s power to auxiliary implements, most often a hydraulic pump.
A hydraulic power take-off system transforms the vehicle’s or machine’s engine power into hydraulic power. And this is the potential that hydraulic pressure and oil flow create.
An electric power take-off is a lever or switch found in farm machinery.
It can be a mechanical engagement or an electric switch taking the engine power, directing and transforming it into the energy and potential required for operating the mower deck or some other implement.
And it can run mowers by either a shaft or a belt.
Nowadays, many farmers switch to electric power take-offs instead of hydraulic ones.
The main reasons for this, according to them, are reduced noise and vibrations, nuisance and danger of shafts, and better efficiency of electrical motors.
Also, you can change the start-ups, fuel savings, and almost an infinite range of rotation speeds and rpm instantly.
Hence, these systems also mean advanced flexibility, more precise operations, applications, and more accurate stops and starts.
What is a tractor PTO shaft?
Tractor PTO shafts supply mechanical energy between the tractors and their implements.
The PTO shaft is an important part of the energy that transforms the engine’s energy into hydraulic pressure.
However, the PTO shaft requires a daily check, as it’s applied to pull the components, and its deprivation can damage and defect the PTO mechanism.
In addition, the PTO shaft is too robust, so you must use it properly.
Main PTO shaft types
You can encounter the following PTO shaft models:
1. Transmission PTO shaft
The oldest and the most specific PTO shaft category.
This category of PTO shafts directly connects the machine to the transmission.
As the PTO shaft engages the PTO system on the tractor, you cannot drive in the PTO once you press the clutch.
2. Live PTO shaft (two-stage clutch PTO Shaft)
This shaft includes two stages of the transmission clutch.
Once you step on the clutch halfway or depress it halfway, the first stage allows you to use the PTO shaft.
On the other hand, the second stage will enable you to command the PTO system. Thus, you can disconnect the transmission and protonation of the PTO shaft operation.
3. Economy PTO shaft
These PTO shafts allow your tractor to run at lower rpm, 540 rpm.
In addition, the PTO shafts save fuel, reduce vibrations, and reduce noise.
Finally, the economy PTO shafts are ideal for numerous equipment for mowing, bailing, or tilling.
4. Independent PTO shaft
These PTO shafts are controlled by the tractor’s transmission, as they come with their clutch.
This shaft has two main types: mechanical and hydraulic.
5. Reverse PTO shaft
This shaft is applied for a tractor driving in the reverse direction by pressing the button.
We use the shaft when the agricultural components get stuck, so it’s almost impossible to perform farm jobs.
Main PTO shaft components
It’s crucial to understand the horsepower, measure, sizes, and shape of the PTO shaft parts to choose the correct shafts for your machines.
So, the most important parts of the PTO shafts include five major PTO shaft parts, such as:
- Safety shields: These are the cones of the shafts found on both ends of the units.
- Safety chains: We apply the chains to connect and secure the tractors and the PTO shafts better.
- External yoke: Two outer yokes are located at both ends of the PTO shaft. The yokes have a “Y” shape, used to connect the female hole with the U-joint.
- Universal joint: Two U-joints are located at both ends of the shaft.
- Internal yoke: You can find two yokes at both ends of the PTO shafts – the implement and the tractor.
Two main shaft types
Many farmers don’t pay too much attention to the content and shape of the shafts until it’s time to change them.
To correctly pick the PTO shaft, you need to determine and check its shape. Regardless of the type, the secondary shaft and the front shaft are the same.
Still, you will find the front shaft more massive, offering a place for the secondary shaft inside. So, according to the shape, there are two main shaft types:
- Metric – shafts are in the shape of a bell, star, or football.
- Domestic – the shafts are in one of the following shapes: splined, rectangle, square, or round.
Metric shafts with bells and stars are standard in Germany, but precisely bell shapes are common in Italy.
On the other hand, the domestic type of square, rectangular, splined, or round shapes is most popular in North America.
Three main PTO types
Depending on the job you need to finish, you will browse for different PTO types.
So, you can find various shafts suitable for mowing, plowing, or shredding, and the equipment and components will resist pressure, impacts, forces, tension, or hits.
So, you can find:
1. Slip clutch – created to prevent your machine and equipment from commonly present obstacles when objects are struck.
For instance, when you encounter rocks and stones, you want to protect the gearbox, so you need a shock-absorbing system to protect your implement.
2. Shear pin – you can use it with an implement such as a chipper.
The end yoke is in two parts, using a shear pin to keep them together while operating.
The pin will absorb the shock, eliminate the sudden stop, and avoid damaging the PTO driveline.
3. Non-shear – ideal for equipment not suitable for any sudden halts.
It has a yoke-to-yoke arrangement. The system is convenient for massive mowers, as their movements are smooth, and there won’t be a problem with resistance or stopping.
Proper sizes
Regardless of the jobs, you will do, the shafts must be of the proper sizes for your needs.
So, the manufacturer should include the length recommendations to consult and get a better insight into the components and their system.
Thus, when measuring the PTO shafts, ensure you use a tape measure and determine from the outside of both yokes to get the closed length.
So, how do the PTO shafts work?
As many models of agricultural implement models lack independent power, this is where the shafts jump in to help to improve the performance.
As the parts have the yokes – connectors at both ends to connect your machinery and implement, you can easily connect all parts and make the complete unit work well.
The shafts work using simple switches. Thus, they can rotate between 540 and 1,000 rpm, depending on the attached equipment.
When in use, the shaft will pull the torque and power from the operating machine transmission to deliver sufficient power and energy to the attached equipment, resulting in a complete performance.
And as we have previously mentioned, if you connect the equipment to the high-torque vehicle and the parts are not incorrect in size and shape, you will damage both the vehicle and the implement.
Thus, you must adequately close the shaft and measure it from yoke to yoke. But, if your PTO shaft is handy, then you can easily confirm the correct size and length.
Where to shop the reliable shaft assemblies and replacement tractor PTO parts?
You can shop all the content, necessary parts, and other sorts of equipment directly on Amazon.
All parts will keep your shafts in excellent condition, but you can also order and shop completely new assemblies to fit your requirements.
Hence, you can refer to Amazon and order:
1. Constant velocity PTO parts – as the constant velocity requires constant speeds in continuous directions, the shafts will work with most implements and tractors.
So, the constant velocity PTO parts will successfully manage and balance the shaft output and tractor’s power input for consistent speeds and higher stability when in use.
2. Half-shaft assemblies – you can find various 48 and 60-inch parts. The parts and assemblies are available in rectangular and square designs.
3. PTO shafts – when you need fully assembled parts, you can also consult Amazon, browse and shop for the best shafts in both North American and Italian style, length, and spline specifications you need.
4. Cross and bearing kits – these parts are the universal joints creating the basics of the PTO shaft’s mechanism.
So, the parts are the crucial points for distributing the power from the tractors to the attached implements.
5. Extra parts – of course, you can save your money and replace the individual components for full content for all shafts that are wear and tear.
Thus, you can find limitless models of the inner tubes, outer tubes, guards, guard bearing, universal clutches, pins, and yokes.
So, once you find the correct missing part, order it directly on Amazon, and they will ship it to your country.
Frequently Asked Questions
How does a tractor PTO work?
As you have already seen, the tractor’s stub shaft, often referred to as the PTO shaft or the PTO, transfers the energy from the high-torque vehicle to the implement attached to it.
In addition, the energy transfer is achieved and accomplished by the connection between the drive shaft of the machinery and the tractor’s PTO shaft.
What are the different types of tractor PTO?
The most common types of the PTO mechanism are the following five. They include:
- reverse – allowing the vehicle and attachment to go in reverse if they get stuck
- economy – allowing the machine to operate on lower rpm, – 540 rpm, reduce the noise of the vibrations, and save fuel
- independent – with mechanical and hydraulic types, suitable for tractors and precisely controlled from the tractor’s transmission
- two-stage clutch/live – one stage allows you to use the shaft while another one lets you command the system when stepping on and releasing the clutch halfway
- transmission – directly connects the mechanism to the transmission, so when you press the clutch, you cannot drive the PTO
Do all tractors have PTO?
Yes, they do. There are some exceptions, but nowadays, it’s rare to encounter such models.
Especially from 1918, when the Power take-off was first invented, all tractors used the power take-off mechanism for various operations and tasks.
So, nowadays, we have a different compact, utility, row crop, and other tractors with power take-off systems.
Otherwise, they wouldn’t be able to function correctly.
What is a hydraulic PTO?
A hydraulic power take-off mechanism will transform your machine’s or another vehicle’s engine power & energy into hydraulic force.
In addition, the hydraulic power that the hydraulic pressure and oil flow create.
What does a 540 PTO mean?
The 540 Power Take-Off or Economy Power Take-Off means a mechanism allowing operators to select the engine RPM needed for their Power Take-Off application.
Thus, the Economy category provides 540 rpm to the power take-off mechanism at the 1700 rpm engine.
Besides, it will save fuel and reduce vibrations and noise while operating.
Final thoughts
And, here we are. This is the end of our PTO trip.
I hope you learned various crucial facts and features the power take-off parts bring, how they work, and why they are essential for tractors.
So, take your time to sift through the guidelines and pick the best power take-off parts for your farm machinery!
Still, pay attention to all tractor PTO types, sizes, shapes, categories, and other essential characteristics the units offer to be able to find the most reliable ones for your tractors.
And, once you determine the critical positions, you’re ready to go. Hence, enjoy the search!