Authored by: Tractor tyre expert | 29 November 2025
Choosing the best tyres for a self-propelled sprayer equipped with wide-span spray booms has never been a simple task. Depending on the weight of your machine when loaded, the size of the booms, or even whether it operates in small or large-scale areas, the requirements in terms of the tyres vary significantly.
For a long time, using narrow tyres to pass between the rows was considered to be the best solution. Yet when the volumes transported and the treatment width increase, their limits soon become apparent.
A latest generation self-propelled sprayer is nothing like an implement drawn by a tractor: the capacity, speed, stability and productivity are on a different scale.
But how do you know which tyre is really suitable for your self-propelled machine? And above all, what technical criteria should you look for in order to make a sustainable and high-performance choice?
In this article we will work through these questions, compare situations, analyse the actual field constraints… and guide you towards the most efficient tyres for self-propelled wide-span machines.
Narrow tyres have long been considered as the most viable solution for spraying operations, in particular when working between the rows with young seedlings.
On a tractor equipped with a mounted sprayer, they make it possible to preserve the seedlings by crossing the field without squashing part of the crops.
Their minimal width limits the part of the ground impacted and guarantees a precise passage, which is essential for small plots of land, closely sown row crops or intervention at the beginning of the plants’ growth cycle.
Thanks to their specific design and to technologies such as the steel belt, certain narrow tyres can bear heavy loads despite their limited contact patch with the ground.
This sturdiness makes it possible to work with a sprayer with a good capacity while preserving the crops.
On polycropping farms, in market gardening or in configurations where passing between rows is indispensable, they retain their interest.
However, these advantages reach their limits rapidly when the volumes loaded onto the machine increase, working speed is higher and the width of the booms goes beyond 40 metres.
A modern self-propelled sprayer transports much more liquid, moves faster and must ensure perfect stability to avoid movement of the booms.
In these situations, the load, the load transfer and the scale of the work change.
A narrow tyre, even a reinforced one, no longer provides the bearing capacity, the stability or the reliability necessary to get the most from a self-propelled wide-span sprayer.
Modern self-propelled sprayers, equipped with 40 to 48 metre or even longer booms are not comparable with a basic tractor equipped with a sprayer, whether mounted or drawn.
They are designed to cover large surface areas rapidly, transport high volumes and move at speed.
In this context, fitting wider tyres is not only pertinent, but often indispensable if you intend to get the most from these machines. This is why.
Phytosanitary treatments are subject to strict meteorological constraints: wind, rain or too much humidity can block an operation in a few minutes.
Self-propelled wide-span machines are chosen specifically for their ability to act fast.
With a wider tyre, the self-propelled machine works quicker, keeping its stability and precision, even on more fragile land or wet land after a shower.
A self-propelled wide-span sprayer treats 40, 42, 48 metres or more with each passage.
So each return trip covers a very large surface area, thus reducing:
In this context, losing a row or two under the tyres does not have the same impact as with a tractor fitted with narrow tyres.
The gain in terms of time, energy and improvement in the overall bearing capacity easily makes up for the loss of an inter-row reserved for tyres over a few lines only.
The longer the booms, the greater the stability constraints: oscillations, load transfer, tank movement during acceleration and braking…
Wide tyres offer a much more stable base thanks to:
Self-propelled machines now transport much higher volumes, so there is more weight than for a tractor and tank.
To cope with this mass – full tank, booms deployed, variations in load in line with the spraying process – wide tyres are a better size.
Their higher load capacity and bigger footprint make it possible:
This is a technical necessity, not just a comfort choice.
Less passes, faster work, more volume transported: wide tyres on a self-propelled machine perfectly satisfy the needs of large farms, agricultural contractors and all farmers who have to treat large surfaces rapidly.
For fields of several dozen hectares where the distances and work rate are decisive, wide tyres are simply more logical.
Self-propelled wide-span sprayers impose extreme constraints and in this demanding environment not all tyres are equivalent.
Firestone’s Radial Deep Tread 23 (RDT23) is clearly the most reliable and efficient solution for equipping self-propelled machines with booms of 40 metres or more.
Fitted with a size 480/80 R50 IF RADT 23 tyre, the RDT23 allows you to reach a load capacity of around 5,300 kg per tyre, i.e. 21,200 kg for a self-propelled machine with 4 equal sized wheels at an inflation pressure of 2.4 bar and a driving speed of up to 40km/h.
This sturdiness is indispensable in order to handle:
This high load capacity stems from the reinforced radial construction and the tyre engineering which allows the tyre to carry more weight at the same inflation pressure or reduce the pressure for the same weight.
The 23° lug angle design used for the RDT23 tyre is not for the sake of looks; it plays a crucial role:
Self-propelled sprayers work at speeds much faster than a tractor carrying a tank.
The RDT23 is designed for:
The size of the booms (40, 42, 48 m or longer) necessitates irreproachable stability: the slightest oscillation can lead to an irregular application, excess consumption of inputs or the risk of insufficient dosing.
The RDT23 meets this challenge thanks to:
THE RESULT? More stable booms, a more precise application of the product and an optimal performance of the self-propelled sprayer, even in difficult conditions.
As we have seen, narrow tyres are still pertinent for average size plots of land or passing between the rows with young seedlings.
But as soon as you move up to a heavy, fast-moving self-propelled sprayer with booms of 40 metres or more, wide tyres become the logical solution: better bearing capacity, better stability, less passes, less compaction, quicker working speed and safer management of variations in load.
And among the solutions, the Firestone Radial Deep Tread 23 is the undisputed leader. It allows you to get the most from a powerful self-propelled sprayer, to ensure precise application of the inputs, to improve road handling and reduce the constraints linked to intensive operations.
For agricultural contracting firms, large farms or any structure working on large surface areas, this level of performance becomes a true lever for productivity.
With Firestone, you have the guarantee of tractor tyres that deliver a real advantage, and that in choosing our brand, you can work worry-free.
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