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Our Agricultural & Farming Tyre section covers key sizes for radial & crossply tractor tyres, along with key farming flotation & implement tyres. Tyres for agro-industrial use on telehandlers, telescopic forklifts & other non-field based machinery may be listed instead in our plant & construction section. We recommend using the 'All Applications' option in our tyre finder if you wish to search across all sectors.

Search our agri & tractor tyre range using our tyre finder below, all you need is your tyre size to start. Ensure you later filter your results to only display tyres that match or exceed your current tyres ply, load & speed rating. Change the 'Agri & Farming' filter option to 'All Applications' to conduct a broader tyre search if you don't find your required tyre initially.

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Your tyre size will almost always be written on the sidewall of your tyre. For tractor tyres it would look something like '16.9-28' or '420/85R28'. The first marking, 16.9-28, is an older imperial format / marking found on crossply tyres, and has numbers written in inches. The second format, 420/85R28, is a more modern radial metric tyre size marking using mm and inches.

In both formats the last number is always the 'rim diameter' (the hole in the middle of the tyre) in inches. In our example the rim diameter is 28 inches. In both formats the first number is the tyre 'width' (also know as its section width), and in our example means the tyre is 16.9 inches or 420mm wide. The 'R' if presents means the tyre is of 'Radial' construction, whereas a '-' indicates the tyre is of 'Crossply' construction.

Modern radial metric sizes, i.e. 420/85R28, include the tyre 'Profile' percentage in the tyre size marking after the '/', here it is 85% profile, which means the tyre side wall height is 85% as tall as the width of the tyre, i.e. 85% of 420mm. The profile is not often given in imperial markings. 

All tyre size markings, imperial or metric, are not always exact. Manufacturers usually just have to be within 5% of the marked numbers for width/height for the tyre to be deemed legally acceptable for that size. For this reason you can sometime find cheaper budget / value tyres are slightly less wide than premium more expensive tyres, though this isn't always the case. In either circumstance the tyre size is always within the 5% tolerances required to fit onto the normally recommended rims, and the only disadvantages of a marginally narrower tyre would be slightly less traction and potentially less wearable tread life.

Radial tyres are a newer and more modern tyre construction compared to the original crossply design. Radial tyres were invented in 1946 and allow the sidewall of the tyre and the tyre tread to work as two independent features. This gives more flexibility to the tyre as well as increasing the tyres strength. Radial tyres can absorb impact shocks and bumps more effectively than crossply tyres can.

Radial tyres give a more comfortable ride which can often allow the driver to work longer. The flexibility of a radial tyres sidewall enhances vehicle stability and provides maximum contact between the tyre and the road surface. This improved contact with the ground reduces the wear on the tyre tread meaning radial tyres last longer than crossply tyres. It also helps spread the weight over the ground reducing soil compaction. Radial tyres tend to have higher speed ratings as they can dissipate heat better, so for some faster road going machines Radial tyres are the only usable option.

A downside of Radial tyres can be the intial cost, as they do tend to be more expensive than crossply alternative. Radial tyres should be viewed as an investment that will pay off in the long run.

Crossply tyres have been around a lot longer and whilst don't offer the many advantages of Radial tyres, they are cheaper, and in some applications are the preferred choice. Crossply tyres have stiffer tyre sidewalls than radial tyres, and so tend to be better at avoiding sidewall punctures, something that is advantageous in forestry use for example. They also give less suspension than Radial tyres which can be an advantage on forklift trucks and scissor lifts for example, where too much suspension can cause loads to become unbalanced.

Ply Rating's are usually only given on tyres of Crossply construction, the newer Radial tyres should have a load index number given instead. A Ply Rating is similar to a tyre Load Index and is an indication/measure of a tyre's strength, telling you the maximum weight that the agricultural & industrial tyre can safely carry. Tyres with a higher ply rating carry more weight but cost more due to their superior construction and the extra materials used.

In general, you shouldn't switch to a lower ply rating than you currently have. You can normally increase the ply rating of the tyre used, but bear in mind the higher a tyres ply rating the stiffer a tyres sidewall usually becomes. This can be advantageous in helping to avoid punctures in the tyre sidewall, but may reduce the suspension/cushioning you experience riding your machine.

The exact carrying capacity of agricultural & industrial tyres can vary by axle, speed, pattern, pressure and manufacturer. Tyre manufacturers often provide detailed information on how much weight a tyre can carry in their technical tyre books, so please check the Technical Link of a product or Contact Us if you need help.

Most modern radial agricultural & farm tyres have a speed and load index stamped on the tyre sidewall, sometimes also known as a service index. A tyre's Speed Index is the maximum safe speed that the tyre can be run at, and is represented by a letter from the very slow (A1) to the very fast (Y and beyond). Many tractor tyres are historically slow speed rated at A8 (25mph) or B (31mph). Some newly developed tyres are increasingly starting to be rated at D (40mph). Some high speed tractors may require an E (43mph) rating. 

The Load Index is the maximum weight that tractor & agricultural tyres can safely support. This is represented by a number, and the higher this number is the more weight the tyre can carry. It is imperative for the safety of the vehicle and its occupants that tyres with high enough Speed and Load Indexes are chosen, and you should always check your current tyres rating before replacing it. The table below shows load index values and their corresponding weight in Kg.

Tubed type (TT) tractor & agricultural tyres have a separate tube fitted inside the tyre which is often purchased separately to the tyre. Tubeless tyres (TL) have their own inner liner which prevents leaks from the rim and minimises the damage done by punctures. They therefore do not require a separate tube to be purchased (if you rims are in good condition). Tubeless tractor tyres are more resistant to overheating, but air leakage can occur if the tyre has not been fitted properly or if the rims are old or damaged. 

At Big Tyres we want to take all the hassle out of buying and fitting tyres. We offer a nationwide mobile fitting service where one of our professional fitting partners will come to your site and fit your tractor tyres for you. No matter the size or application we can generally have your new tyres up and running fast. You can add fitting when ordering online, or mention that you require fitting with your tyres when you order by phone, and we will add the cost to your order and take payment. Read our fitting page for more detailed information on how our fitting service works.

Ballasting your agricultural & industrial tyres involves partially filling the tyre or inner tube with water. This is done in order to lower the centre of gravity and stabilise the machine to help it deal with uneven ground.

Over-inflated agricultural & farm tyres can increase soil compaction, fuel consumption and wear to the machine and the tyres. Soil and crops can also be badly damaged, requiring heavy investment to break up the compaction layer. Conversely, under-inflation means that manoeuvrability will suffer and irreversible damage will be done the casings of your agricultural & industrial tyres.

We often get asked about fitting inner tubes in tractor tyres designed to function without an inner tube, often due to the tubeless tyre having a puncture. Whilst an inner tube will hold air and keep your tyre inflated it is not recommended for a couple of reasons. The main reason is for safety, as a tubeless tyre is designed to deflate slowly when punctured so is safer. A tube in a tubeless tyre once punctured can lose air rapidly and if the tyre casing isn't holding air successfully the tyre could deflate very quickly causing a safety hazard if travelling at speed. Also, tubeless tyres have a rougher inner surface and this can rip the tube, or cause friction & heat which can burst the tube.