How tall is a 40x15.50R20 tire?

A 40x15.50R20 has a nominal overall diameter of 40 inches (1016 mm), calculated as the 20-inch wheel plus two sidewalls. This is the unloaded figure — a fitted tire sits fractionally shorter under the weight of the vehicle.

What wheel size does a 40x15.50R20 tire fit?

A 40x15.50R20 fits a wheel of 20 inches in diameter. The wheel also has to be within the rim width range the manufacturer publishes for this size, which is printed in the tire's spec sheet.

What do the numbers in 40x15.50R20 mean?

This is a flotation size, quoted in inches rather than millimetres. 40 is the overall diameter, 15.5 is the section width, R marks the construction (radial), and 20 is the wheel diameter.

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Size Dimensions & Specs

Tires Size 40x15.50R20

Dimensions, specs, and every size 40x15.50R20 tire currently in stock

Overall Height

40"

1016 mm · calculated

Section Width

15.5"

stated in inches

Sidewall Height

10"

254 mm

Wheel Diameter

20"

508.0 mm

40x15.50R20 Specifications

Read directly from the size code. Load index, speed rating, and rim width range vary by model.

Specification	Imperial	Metric
Section width	15.5 in	—
Sidewall height	10 in	254 mm
Overall diameter (calculated)	40 in	1016 mm
Wheel / rim diameter	20 in	508.0 mm
Construction	Radial	—

What does 40x15.50R20 mean?

Reading the code on your sidewall

Overall diameter

40 in

Flotation sizes lead with the tire's full height in inches rather than a width in millimetres.

Section width

15.5 in

The width across the widest point of the tire, also quoted in inches on this style of size.

Construction (R)

Radial

The body plies run across the tire at right angles to the direction of travel.

Wheel diameter

20 in

Fits a wheel measuring 20 inches across.

40x15.50R20 Questions & Answers

Dimensions and fitment guidelines for size 40x15.50R20

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