40X13.50R17LT Tire Size

All You Need to Know About 40X13.50R17LT Tires

A 40X13.50R17LT tire is the Light Truck version of the large 40-inch radial flotation size. It carries the same nominal 40-inch diameter and 13.5-inch section width as the standard 40X13.50R17, but the LT designation signals a heavier-duty casing - one built specifically to support greater loads, handle towing stress, and sustain hard off-road use under weight.

At a 40X13.50R17LT tire size, the load capacity and casing strength difference between an LT and a non-LT tire is meaningful: a 40-inch tire already puts significant stress on hubs, bearings, axle shafts, and steering components, and LT construction provides a structural margin that the standard flotation casing does not.

40X13.50R17LT Size Quick Specs

The following specifications apply to 40X13.50R17LT. Actual inflated diameters and load/inflation figures vary by specific tire model; always verify against the manufacturer's published specifications.

What LT Means on 40X13.50R17LT

The LT on 40X13.50R17LT identifies this as a Light Truck service tire under TRA and DOT classification. Compared with a standard flotation 40X13.50R17, the LT construction provides:

• Higher per-tire load capacity - the stronger casing supports more weight per tire, which matters on heavy diesel trucks, armored vehicles, and vehicles towing
• Stiffer casing with more ply layers - Load Range D carries 8-ply equivalent reinforcement; Load Range E carries 10-ply equivalent, each with greater resistance to sidewall deformation under load
• Higher rated maximum inflation pressure - LT-rated tires in this size operate at higher PSI ceilings, which increases the effective load capacity of each tire
• Greater sidewall puncture resistance - the heavier ply construction resists cuts and impacts from rock edges and trail debris better than a lighter flotation casing
• Firmer ride under load - the stiffer LT casing reduces sidewall flex at normal operating pressures, which produces a firmer ride feel compared to the standard 40X13.50R17

40X13.50R17LT vs 40X13.50R17: What the LT Adds

The following table compares 40X13.50R17LT against the standard flotation 40X13.50R17 - two tires with identical nominal dimensions but different service category and casing construction.

40X13.50R17LT vs 42X13.50R17LT - Size Comparison

Both 40X13.50R17LT and 42X13.50R17LT are LT-rated radial flotation tires on 17-inch wheels in the 13.5-inch section width family. The following table shows the dimensional relationship between the two sizes.

The 42X13.50R17LT is two inches taller in nominal diameter than the 40X13.50R17LT, adding approximately 1 inch of axle clearance. The step from 40 to 42 inches is not trivial - the 42-inch tire's larger circumference requires more aggressive gearing correction, imposes greater steering load, demands more braking capacity, and on most platforms requires additional suspension and body clearance modifications beyond what the 40-inch tire already demands.

For the standard flotation (non-LT) version, see 40X13.50R17. For the bias-ply version, see 40x13.50-17.

Who 40X13.50R17LT Is For

40X13.50R17LT tires are appropriate for vehicles that combine a 40-inch tire requirement with significant weight, payload, or towing demands:

• Heavy diesel trucks running 40-inch tires - the LT casing supports the higher GVWR of these platforms
• Rock-crawling builds carrying payload: armor plating, auxiliary fuel tanks, recovery gear, and roof-mounted equipment all add weight that standard flotation load ratings may not adequately support
• Expedition trucks that operate off-road while carrying extended-range gear weight
• Towing applications at the 40-inch size - the LT rating provides the load index margin needed for trailer tongue weight and full payload

40X13.50R17LT is not the right choice for factory-height vehicles, lightly modified daily drivers, or builds where ride comfort at this size is the priority. Standard flotation 40X13.50R17 tires are better suited for lighter builds that do not require the higher load capacity of an LT casing.