Tire ply rating and load range: what LT tire load ranges mean and how to choose the right one

What does tire ply rating and load range mean?

Ply rating originated as a count of the cotton fabric layers (plies) in the tire carcass — more plies meant higher load capacity and higher pressure capability. Modern steel-belted radial tires 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 tire sidewall rather than an LT-style load range letter.

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 tires 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 Historical reference only.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 tire 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 tires: a direct comparison

Aspect LT tire P-metric tire Practical implication
Tire 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 tire 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 tire 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 tire than a P225/75R16. Lower. P-metric tires 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 tires, 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 tires typically operate at 30–44 psi (2.0–3.0 bar). Never inflate an LT tire 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 tires typically have more wear remaining when wear indicators appear on P-metric tires.
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 tires regardless of vehicle type.

Example load capacities by size and load range

Tire 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 tires

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 tires are not rated for use on powered axles or as passenger vehicle tires. They have a higher load capacity than an equivalently sized LT tire because trailer use involves no driving or braking forces. ST tires are speed-rated differently — typically 65 mph (105 km/h) at their rated load. Some trailer tires 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 tires (P-metric and Euro-metric, without the LT designation) use a simpler classification instead of load range letters:

XL/Reinforced tires 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 tire with another XL — fitting a standard load tire 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 tire, the load range appears after the size description, before or after the load and speed index. Example: LT265/70R17 121/118R E — here:

On European commercial tires, 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 tire with Load Range C construction.

Choosing the right load range

Always match or exceed the load range specified on the vehicle's tire placard. The placard is set by the manufacturer to meet the vehicle's GVWR (Gross Vehicle Weight Rating). Key rules:

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Last reviewed: 2026-06-22

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