Liquid ballast vs wheel weights

Your tractor tyre model determines your load capacity. Agricultural tyres are solid, but not sufficiently so to cope with any level of load and you must take this into account when it comes to choosing your ballast.
Adding too much weight to your combination vehicle can effectively be counterproductive, so you need to choose the additional weights necessary carefully to improve the efficiency of your tractor. You have several options; water ballast, wheel weights or adding additional ballast masses to the front or rear lift.
All these operations can be combined and result in you obtaining the right balance for your vehicle. If you leave the role of balancing the weight of the rear implement to ballast on the front lift, you can focus on the wheels and try to define what will be most effective between liquid ballast or the use of additional wheel weights.

In this article we compare the two methods of ballasting your wheels, to help you choose which is most effective and best suited to your particular situation.

1. What is the purpose of ballast at the level of the tractor wheels or tyres?

The main aim is to establish balance between weight and tractor power. Depending on your tractor’s power and the implement used, it may be necessary to complete the weight of the front lift by adding additional masses to the wheels.

It is important to find the best possible balance by spreading the weight over the whole tractor as far as possible.

When you have obtained stability, the tractor can use its power efficiently on the ground with the same effort from the 4 drive wheels, without overloading the tyres or the transmission system.

The advantages of good ballasting

Having the best ballasting possible ensues the most efficient use of your agricultural equipment and improves your safety. Below are the main advantages when working:

• Improved traction
  A properly ballasted tractor is more efficient, which generally leads to optimised traction. This is indispensable for transporting heavy loads in the fields, or working with high torque on difficult terrain.
• Reduced slip
  Good ballasting reduces slip by ensuring that all four wheels grip the ground better. By ballasting your wheels or tyres correctly, you avoid loss of power and fuel caused by excess slip while preserving the soil structure.
• Decrease in rolling resistance
  Suitable ballasting contributes to reducing rolling resistance. Correctly ballasted tyres sink into the ground less, generate less friction with the soil, which reduces your fuel consumption and premature wear.

The consequences of bad ballasting

On the other hand, unsuitable ballasting leads to major problems: reduced work efficiency, soil damage and increased fuel consumption.

If there is too much ballast, the tractor sinks into the ground, rolling resistance increases, leading to excess fuel consumption. The tyres are placed under too much strain, are crushed by the weight of the machine and will deteriorate rapidly as their casing becomes misshapen.

If there is not enough ballast, the front axle does not grip the soil sufficiently, due to insufficient weight the steering is not very responsive and the tyres are likely to wear very rapidly. For example, in the image below, this badly ballasted tractor is not getting enough grip. As the weight of the machine is insufficient compared to the weight of the implement, the tractor is making no headway.

2. Water ballasting tractor tyres

Water ballasting consists in filling up the tyres with water to add weight to improve the tractor’s grip on the ground and its stability.

What are the advantages of water ballasting?

• It’s the most economical form of ballasting
  Water ballasting offers an economical way of improving the adherence of your tractor tyres. This method, less costly than using metal weights, allows you to ballast your tractor without any negative effect on your budget.
• Easy to implement
  This technique is relatively easy to implement and does not require any additional equipment. Using water and antifreeze, the ballasting can be carried out very simply.
• Ballasting that is always proportional
  Once completed, water ballasting offers an even spread of the weight over the tractor axles. You are sure not to get the additional weight wrong because it is in perfect proportion with the size of your tyres and as such with the power of your tractor. No risk of overloading.

Examples of water ballasting based on tyre size

The drawbacks of water ballasting:

There are also drawbacks which are rarely taken into account because the objective of economical ballasting takes precedence over all the other problems. However, it is not always the best solution. Here’s why:

• A permanent dead weight
  Water ballasting is generally carried out for the entire season. If you use your tractor regularly for transport by road, for example, the dead weight of the water mass will be permanent, even when it serves no purpose. This leads to unnecessary fuel consumption, which can represents several thousand euros in net losses over the year.
• Unsuitable ballasting
  Water ballasting is even, involving a mass that is in proportion with the size of the tyres, but not with the real weight of your vehicle’s implements. It may be excessive if the implements are light or insufficient for heavier implements.
• Less comfortable when driving
  This ballasting technique may make the tyre less comfortable to use. Water is effectively less compressible than air, which makes the tyre rigid and means that it loses its role as a natural shock absorber. This can lead to discomfort when driving, especially on rough terrain.
• Safety risk on the road
  On the road, water ballasting can cause problems due to the swinging effect caused by the movement of the water within the tyres. This swaying can affect road and tractor handling capacities, especially at speed, during sudden braking or when turning.
• Loss of pressure
  With water ballasting the management of tyre pressure becomes more complex due to the low proportion of air left in the tyre. The slightest loss of air will have a rapid impact on tyre pressure. You will therefore need to check pressure much more regularly to ensure it stays at the right level.

3. Ballasting with additional wheel weights

Another ballasting technique consists in adding metallic weights to the tractor wheels. This methods improves the adherence to the ground for each axle as well as traction and the overall stability of the agricultural vehicle, especially with heavy loads or when working on rough terrain.

The benefits of ballasting with additional wheel weights

Better overall performance

Ballasting with additional wheel weights leads to better overall efficiency due to its precision. It allows for a very precise distribution of weight to the wheels, improving adherence and traction depending on the implements used on different types of agricultural land.

Removeable and adaptable

Additional wheel weights can be removed and are adaptable. This means that you can easily adjust the quantity of ballast depending on your implements, the work to be done or the weather conditions. This adaptability optimises the operational efficiency of your tractor throughout the year, ensuring top performance levels in all conditions.

What are the drawbacks of additional wheel weights?

Despite many advantages, there are several drawbacks to ballasting with additional wheel weights.

• A higher cost
  This practice is often more expensive than other methods of ballasting, such as water ballasting. It is therefore less attractive for farmers with tight budgetary constraints.
• Excess fuel consumption
  If you don’t take the time to remove the metal weights from the wheels when they are not needed, you will be driving with overloaded axles which will lead to excess fuel consumption.
• Excessive soil compaction
  Ballasting with additional wheel weights can cause excessive soil compaction. When the axles are overloaded, the pressure exerted on the ground is higher, which leads to compaction of the different layers of soil.

4. Water ballasting vs wheel weights: which is the winner?

When you look closely at water ballasting of tractor tyres versus use of additional wheel weights, you must take into account the pros and cons of each method.

Water ballasting of front tyres is less efficient

Ballasting front tyres with water may seem a practical solution, but in reality it is not very efficient due to the small volume of water that can be added.

Using ballast masses on the front wheels is much more effective because it allows you to add more weight. This method effectively allows the weight to be distributed more precisely, which improves traction and the overall stability of the tractor.

In addition, it offers greater flexibility in terms of adjustment of the weight to lighten the load when ballasting is unnecessary.

What is the best way of ballasting rear tyres?

Ballasting rear tyres is always very effective in improving productivity. With this in mind, ballasting with additional wheel weights emerges as the most interesting option.

Why?

Because you can add the exact additional weight required without your tyres becoming rigid, unlike water ballasting which represents 75% of the volume of the tyre.

Ballasting with wheel weights also has the advantage of the weights being removable and easy to adjust and being used in combination with ballast masses fixed to the front lift. The ballast can be added or removed in line with your needs or the weight of your implements, which contributes to better overall tractor performance.

This is not possible with water ballasting which requires on average 2 to 3 hours to fill up your tyres if you have a specific ballasting pump and the same time for emptying.

As ballasting using wheel weights is better adapted to the real mass of your combination vehicle, it leads to better traction in the fields, a greater reduction in slip and an improvement in work efficiency.

To find out more and extend the lifespan of your tractor tyres, download our free comprehensive guide: “How to adjust the pressure in my tractor tyres to gain hours more use”.

Most people who read this article have also read some of the following articles:

• Key explanations on load and agricultural tyre ballasting
• You want to know everything about water ballasting your tractor tyres
• Is your ballast really suited to your tractor tyres?