Tyre ply rating and load range: what LT tyre load ranges mean and how to choose the right one
What does tyre ply rating and load range mean?
Ply rating originated as a count of the cotton fabric layers (plies) in the tyre carcass — more plies meant higher load capacity and higher pressure capability. Modern steel-belted radial tyres no longer use multiple cotton plies, but the term survives as a load capacity classification. Load range letters — C, D, E, F, and G — replace the old ply-count system. Each load range letter corresponds to a specific maximum inflation pressure: Load Range C is 50 psi (3.45 bar), D is 65 psi (4.5 bar), E is 80 psi (5.5 bar), F is 95 psi (6.6 bar), and G is 110 psi (7.6 bar). Higher load range means a stiffer carcass capable of carrying more load at higher pressure — important for light trucks, vans, and tow vehicles. For most passenger cars, load range is expressed differently, using the load index on the tyre sidewall rather than an LT-style load range letter.
- Ply rating originated as a count of the cotton fabric layers (plies) in the tyre carcass — more plies meant higher load capacity and higher pressure capability.
- Modern steel-belted radial tyres no longer use multiple cotton plies, but the term survives as a load capacity classification.
- Load range letters — C, D, E, F, and G — replace the old ply-count system.
FAQ
- What does tyre ply rating and load range mean?
- Ply rating originated as a count of the cotton fabric layers (plies) in the tyre carcass — more plies meant higher load capacity and higher pressure capability. Modern steel-belted radial tyres no longer use multiple cotton plies, but the term survives as a load capacity classification. Load range letters — C, D, E, F, and G — replace the old ply-count system. Each load range letter corresponds to a specific maximum inflation pressure: Load Range C is 50 psi (3.45 bar), D is 65 psi (4.5 bar), E is 80 psi (5.5 bar), F is 95 psi (6.6 bar), and G is 110 psi (7.6 bar). Higher load range means a stiffer carcass capable of carrying more load at higher pressure — important for light trucks, vans, and tow vehicles. For most passenger cars, load range is expressed differently, using the load index on the tyre sidewall rather than an LT-style load range letter.
- What should I verify before using this information?
- Use TireFitLab values as a sizing reference, then verify the vehicle handbook, tire placard, rim compatibility, load rating, and physical clearance before fitting.
Load range letters and maximum inflation pressure
| Load range | Ply rating equivalent | Maximum inflation pressure | Notes |
|---|---|---|---|
| B | 4-ply equivalent | 35 psi / 2.4 bar | Passenger car standard load. Rarely stated explicitly on the sidewall — normal P-metric tyres without an LR designation are Standard Load (SL) or Extra Load (XL/RF). Historical reference only. |
| C | 6-ply equivalent | 50 psi / 3.45 bar | Light duty. Common on small vans, trailers, and some pickup trucks. Sidewall is noticeably stiffer than a passenger car tyre of the same size. |
| D | 8-ply equivalent | 65 psi / 4.5 bar | Moderate duty. Larger vans and trailers, lighter pickup truck applications. Less common than C or E. |
| E | 10-ply equivalent | 80 psi / 5.5 bar | The most common LT load range for full-size pickup trucks (e.g. Ford F-150, RAM 1500, Toyota Tundra). Provides the load capacity and durability expected for regular towing and payload. |
| F | 12-ply equivalent | 95 psi / 6.6 bar | Heavy duty pickup and light commercial. Used on vehicles with maximum payload ratings or regular near-GVW operation. Very stiff sidewall — ride quality on light loads is harsh. |
| G | 14-ply equivalent | 110 psi / 7.6 bar | Very heavy commercial use. Some medium truck and severe service applications. Rarely found on consumer vehicles — found on heavy commercial vans and specialist off-road vehicles. |
LT vs P-metric tyres: a direct comparison
| Aspect | LT tyre | P-metric tyre | Practical implication |
|---|---|---|---|
| Tyre designation | Prefixed with "LT" — e.g. LT225/75R16 E | Prefixed with "P" or no prefix — e.g. P225/75R16 or 225/75R16 | LT designation indicates a tyre engineered specifically for light truck service. |
| Sidewall construction | Stiffer, multiple-ply equivalent. Designed to handle the flex of heavy loads without heat buildup. | Softer, optimised for passenger comfort. Not designed for sustained near-GVW loading. | An LT tyre in the same nominal size as a P-metric will have a significantly stiffer ride. |
| Load capacity at same size | Higher. An LT225/75R16 E can carry approximately 15–20% more load per tyre than a P225/75R16. | Lower. P-metric tyres must be derated by 10% when used on light trucks (the "LT adjustment factor" in GVWR calculations). | If your pickup truck's placard specifies LT tyres, fitting P-metric reduces your legal load capacity. |
| Inflation pressure | Higher. LR E operates to 80 psi (5.5 bar). The higher pressure is needed to achieve the rated load capacity. | Lower. Standard passenger car tyres typically operate at 30–44 psi (2.0–3.0 bar). | Never inflate an LT tyre to P-metric pressures — you'll significantly underestimate its actual load capacity. |
| Tread depth | Generally deeper original tread for longer wear life under demanding use. | Shallower original tread optimised for wet/dry road performance and noise. | LT tyres typically have more wear remaining when wear indicators appear on P-metric tyres. |
| Off-road durability | Substantially better. Stiffer sidewall resists puncture from rocks and debris. Higher load capacity handles the shock loads of off-road use. | Not designed for off-road use. High risk of sidewall cuts and impact damage. | Any serious off-road use requires LT tyres regardless of vehicle type. |
Example load capacities by size and load range
| Tyre size | Max pressure | Single load (kg) | Dual load (kg) | Notes |
|---|---|---|---|---|
| LT225/75R16 C | 50 psi (3.45 bar) | 925 | 850 | Used on smaller light commercial vans, some trailers. |
| LT225/75R16 D | 65 psi (4.5 bar) | 1030 | 950 | Heavier van applications. |
| LT225/75R16 E | 80 psi (5.5 bar) | 1215 | 1120 | Standard for full-size pickup trucks with LT spec. |
| LT245/75R17 E | 80 psi (5.5 bar) | 1360 | 1250 | Popular truck size — higher load from larger section width and diameter. |
| LT265/70R17 E | 80 psi (5.5 bar) | 1500 | 1375 | Common on 3/4-ton (HD) pickups. Significant dual-wheel payload capability. |
ST — Special Trailer tyres
| Category | Common load ranges | Typical use | How they differ from LT | Speed limitation |
|---|---|---|---|---|
| ST — Special Trailer | C, D, E | Boat trailers, car trailers, livestock trailers, flatbed trailers. | Designed to carry very high loads at lower speeds. ST tyres are not rated for use on powered axles or as passenger vehicle tyres. They have a higher load capacity than an equivalently sized LT tyre because trailer use involves no driving or braking forces. | ST tyres are speed-rated differently — typically 65 mph (105 km/h) at their rated load. Some trailer tyres carry a speed rating that corresponds to lower ratings such as L (75 mph) or M (81 mph). |
Passenger car load ratings: Standard Load and Extra Load
Passenger car tyres (P-metric and Euro-metric, without the LT designation) use a simpler classification instead of load range letters:
- Standard Load (SL) — maximum inflation pressure 51 psi (3.5 bar). This is the default for most passenger car tyres when no special designation appears. Load index values are read at standard inflation.
- Extra Load (XL) or Reinforced (RF) — maximum inflation pressure 51 psi (3.5 bar) but the load index is calculated at a higher reference pressure, giving approximately 10–15% more load capacity than an SL tyre of the same size and load index number. The sidewall will display "XL", "EXTRA LOAD", or "RF."
XL/Reinforced tyres are increasingly specified as OEM on heavier SUVs, electric vehicles (which are heavier than comparable ICE vehicles), and compact cars that are specified with maximum payload. Always replace an XL tyre with another XL — fitting a standard load tyre will reduce the load capacity of that axle below the vehicle's rated capacity.
How to read the load range from the sidewall
On an LT tyre, the load range appears after the size description, before or after the load and speed index. Example: LT265/70R17 121/118R E — here:
- LT — light truck designation
- 265/70R17 — section width, aspect ratio, construction, rim diameter
- 121/118R — load index for single (121 = 1450 kg) and dual (118 = 1320 kg) fitment, speed rating R (170 km/h)
- E — Load Range E (80 psi / 5.5 bar maximum)
On European commercial tyres, you may see C at the end of the size — e.g. 195/70R15C 104/102R. The C suffix is the European equivalent of the LT prefix and indicates a commercial tyre with Load Range C construction.
Choosing the right load range
Always match or exceed the load range specified on the vehicle's tyre placard. The placard is set by the manufacturer to meet the vehicle's GVWR (Gross Vehicle Weight Rating). Key rules:
- Never fit a lower load range than specified — this reduces the safe carrying capacity of the vehicle below its rated GVWR and may create a legal liability in an accident.
- Fitting a higher load range is generally safe but comes with a ride quality penalty. Load Range F on a vehicle specified for Load Range E will ride more harshly because the stiffer sidewall transmits more road irregularities to the chassis.
- Check the pressure — an LR E tyre inflated to LR C pressure will not carry LR E loads safely. The load capacity of an LT tyre is directly tied to its inflation pressure. Always inflate to the pressure shown on the placard for the loaded condition.
More tools
- Tyre load capacity guide
- Load index chart
- Tyre overloading guide
- Tyre pressure for heavy loads and towing
- Tire & wheel reference guides
Seasonal check
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Use the budget and running-cost tools before a trip, especially if the current tyres are worn or the replacement size changes diameter.
What changed
- Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.