Agri Tyre Tread Patterns Explained: R-1, A-W, G-2, L-5 and R-4
The letter-number code on an agricultural tyre is a standardised classification — not a brand designation. Understanding what R-1, R-4, A-W, L-5, and G-2 mean before you order prevents a fitment mistake that can cost a full season's field efficiency.
The Tread Code System
Agricultural and construction tyre tread codes follow a classification defined under SAE J709 and ASABE S390. Each code has two parts: a letter indicating the equipment class, and a number indicating the relative tread depth within that class.
The letter codes relevant to farm and construction equipment:
- R — Rear tractor drive wheel
- F — Front tractor (steer) wheel
- I — Industrial (general purpose)
- L — Loader (wheel loaders, skid steers)
- G — Grader (motor graders, telehandlers, backhoes)
- A-W — All-weather implement (trailer and towed equipment)
For R, G, and L class tyres, a higher number means deeper lugs — with one important caveat: the depth scale resets between classes. An L-5 is not deeper than a G-2 in absolute terms; each scale is relative to its own class baseline.
R-1 — Rear Tractor Field Pattern
The R-1 is the standard rear tractor drive tyre for field work. Its distinguishing feature is the deep, widely-spaced chevron or V-lug block: lugs are set far apart so that as each lug exits the contact patch, it sheds the soil or paddy water it has collected — the next lug enters clean. This self-cleaning action is what makes R-1 effective in the conditions that would stall most other patterns.
R-1 is the correct choice for any primary field operation: soil tillage, seeding, transplanting, harvesting on soft to medium ground. Black cotton soil, laterite, paddy fields, and soft farm roads are its home terrain.
R-4 — Industrial OTR Pattern
R-4 lugs are shallower and more closely spaced than R-1 — approximately 50% of R-1 lug depth. This makes R-4 a substantially different product despite the similar code: it is engineered for hard surfaces, not soft ground.
On compacted earth, gravel roads, and construction sites where the ground does not yield under load, the deep open lugs of an R-1 wear out rapidly and provide no more traction than a shallower pattern. R-4's denser, shallower lug wears evenly on abrasive surfaces and handles mixed hard-surface conditions more efficiently.
The trade-off is absolute: R-4 on soft, loose, or wet ground will spin and sink. It does not self-clean, and the shallower lugs cannot generate the bite needed for field traction. Fitting R-4 to a rear tractor axle for paddy or soil work is a common and costly mistake.
Correct applications for R-4: motor grader drive wheels, OTR loaders, and any equipment that operates predominantly on hard or mixed construction surfaces.
A-W — All-Weather Implement Pattern
A-W is not a drive tyre. It is a load-bearing implement and trailer pattern designed for towed equipment — farm trailers, wagons, combine header trailers, and implements that roll on farm roads and fields but never drive themselves.
The transverse rib design minimises rolling resistance and provides stable, predictable load-bearing at speed. The A8 speed rating (40 kmph) makes it suitable for trailers used on district roads and inter-farm transport, not just field headlands.
Fitting an A-W to a drive axle will result in immediate wheel spin under any traction load. The flat rib generates almost no lateral traction — that is by design. The pattern exists to carry load smoothly, not to push the machine forward.
L-5 — High-Lug Loader Pattern
The L-class rates loader tyres by lug depth: L-2 is the standard loader depth, L-3 is deep, L-4 is rock, and L-5 is extra-deep rock. L-5 carries the most rubber between tread surface and carcass of any loader class pattern.
This extra lug depth exists as a wear reserve for the most destructive surfaces: sharp laterite, quarry aggregate, stone-base yards, and any environment where conventional lugs would chunk or abrade to the casing rapidly. On a standard construction site, L-5's extra rubber is unnecessary cost. On a hard rock quarry face or aggregate plant, it is the only pattern that gives acceptable service life.
L-5 is used on skid steers, compact wheel loaders, quarry loading shovels, and waste-handling equipment on highly abrasive surfaces.
G-2 — Grader and Telehandler Pattern
G-class tyres rate tread depth for grading equipment. G-1 is shallow (on-road use), G-2 is medium (compacted earth and gravel), G-3 is deep (off-road and heavy earthwork). G-2 is the standard construction-site fitment precisely because it sits in the middle: enough lug depth for traction on compacted earth, shallow enough to resist rapid wear on the mixed surfaces construction equipment encounters in a single shift.
Where R-1 maximises soft-ground traction at the expense of wear resistance, G-2 accepts a traction compromise to achieve acceptable wear life across variable terrain. For equipment that transitions from soft clay to compacted haul road and back multiple times per day — as a backhoe loader or telehandler typically does — G-2 is the practical choice.
G-2 is the standard rear fitment for backhoe loaders and the drive fitment for telehandlers and motor graders on construction sites. It is also used on tractors deployed for road maintenance and light earthwork rather than primary field operations.
Pattern Comparison at a Glance
| Pattern | Lug depth | Ground type | Drive axle? | Speed rating |
|---|---|---|---|---|
| R-1 | Deep, open | Soil, paddy, clay, farm roads | Yes — rear tractor | A6 / 30 kmph |
| R-4 | Shallow–medium | Compacted earth, gravel, construction | Yes — OTR equipment | B / 50 kmph |
| A-W | Ribbed / flat | Hard surface, farm roads | No — implement / trailer only | A8 / 40 kmph |
| L-5 | Extra deep, blocky | Rock, quarry, abrasive surfaces | Yes — loader drive axle | A8 / 40 kmph |
| G-2 | Medium | Construction site, mixed terrain | Yes — backhoe / telehandler / grader | A2–A8 (size dependent) |
How to Choose
- Farm tractor rear drive — primary field work: R-1. Flooded paddy: R-1W.
- Farm trailer, implement axle, towed equipment: A-W.
- Backhoe loader rear axle: G-2.
- Telehandler or motor grader on construction site: G-2.
- Skid steer or compact loader on rock or quarry: L-5.
- Motor grader or OTR loader on compacted road or hardpack: R-4.
- Tractor deployed for road maintenance or light construction: R-4 or G-2 depending on lug depth needed.