Two loader tyres can be the same size, from the same factory, at roughly the same price, and still last very different numbers of hours on your site. Usually the reason is the short code moulded on the sidewall: L2, L3, L5 and so on. That is the TRA code, a classification developed by the Tire and Rim Association in the United States and used internationally, which tells you what job a tyre was designed for.
Once you know how to read it, it becomes one of the most useful things on the sidewall.
The letter: which machine
| Letter | Machine type | Typical use |
|---|---|---|
| E | Earthmover | Dump trucks, scrapers, articulated haulers: hauling loads over distance |
| L | Loader & dozer | Wheel loaders and wheel dozers: short, slow, heavy loading cycles |
| G | Grader | Motor graders: road building and haul-road maintenance |
| C | Compactor | Rollers and compactors |
The letter also implies a speed range. E tyres are designed to carry load at haul speeds, while L tyres are designed for the slow back-and-forth of loading and are not meant for long, fast runs. G tyres sit in between. This is the part people forget, and it is behind many early failures.
The number: which tread
| Number | Tread | Where it fits |
|---|---|---|
| 1 | Ribbed | Light duty, mainly on graders and some haulers |
| 2 | Traction | Soft ground, sand, clay, where grip is the problem |
| 3 | Rock, standard depth | The general-purpose choice for most construction and quarry work |
| 4 | Rock, deep tread | Abrasive surfaces, more cut protection |
| 5 | Rock, extra-deep tread | Very abrasive or sharp shot rock, mainly loaders at the face |
| 7 | Flotation | Very soft ground where the machine would otherwise sink |
Put the two together: L3 is a loader tyre with a standard rock tread, L5 a loader tyre with extra-deep tread, G2 a grader tyre with a traction pattern, E3 a hauler tyre with a rock tread.
Dual-marked tyres: E3/L3
Many tyres in common sizes like 20.5-25 and 23.5-25 are marked E3/L3. That means the design meets the requirements for both loader and earthmover duty. It is a sensible, flexible choice for machines that do a bit of both, such as a loader that also carries material some distance across a yard, or an articulated dumper.
Why deeper is not always better
It is tempting to think an L5 is simply a "stronger" L3. It is not. A deeper tread has more rubber, and rubber builds heat when it flexes. On a loader doing short cycles at a quarry face, that extra rubber is pure protection against cuts. On a loader that regularly carries material 200 metres to a hopper, the same deep tread runs hotter, and heat is what separates tread from casing.
The rule of thumb many tyre engineers use is simple. Choose the deepest tread that your cycle length and speed allow, and step down a level if the machine travels more.
Matching the code to the job
| Machine and job | Usual starting point |
|---|---|
| Loader at a batching plant or on a paved yard | L2 / L3 |
| Loader feeding a crusher on prepared ground | L3 |
| Loader at a limestone or granite face | L4 / L5 |
| Grader on road construction | G2 |
| Grader maintaining stony haul roads | G3 |
| Rigid dump truck on quarry haul roads | E3 / E4 |
| Articulated dumper on mixed ground | E3/L3 |
These are starting points, not rules. Surface, cycle length, load and how carefully the machine is driven all shift the answer.
Where the star rating fits in
Radial OTR tyres also carry a star rating, one to three stars, which describes load capacity. The TRA code says what the tyre is for; the star rating says how much it can carry in that role. A two-star L3 can carry more than a one-star L3 of the same size, at the cost of a stiffer ride. Bias tyres express the same idea with a ply rating such as 16PR or 20PR.
Practical advice before you order
- Check the code on the tyre you are replacing. If it lasted well, start there.
- If it failed early, look at how. Cuts and chunking point to a deeper tread. Separation and blistering point to heat, and a shallower tread or radial construction may be the fix.
- Keep the same code across an axle. Mixing L3 and L5 on one axle means unequal rolling diameters and uneven load.
- Tell your supplier the job, not just the machine. "5-ton loader at a limestone face" gets you a better recommendation than "5-ton loader".
If you are not sure which code you need, send us a photo of the sidewall and a line about the site. We will tell you what we would fit and why.
Need a price on these tyres?
Send a sidewall photo or your size list. Quotes usually within one business day.