155/80R17 Tire Size

All You Need to Know About 155/80R17 Tires

The 155/80R17 tire is a temporary spare format designed to provide short-term mobility while maintaining a closer rolling diameter to standard tires than lower-profile spare designs.

The 155/80R17 size defines the temporary tire that is 155 mm wide, with an 80% aspect ratio, mounted on a 17-inch wheel, resulting in an overall diameter of ≈ 26.8" and a sidewall height of 124 mm (≈ 4.9").

Because of this taller structure, the 155/80R17 (≈26.8" OD) sits closer to full-size tire diameters than compact spare variants. For example, it is measurably closer to smaller OE 17-inch fitments such as 215/50R17 (≈25.5") and 205/55R17 (≈25.9"), reducing rotational difference.

By comparison, compact spare sizes like 125/70R17 (≈23.9") and 135/70R17 (≈24.4") are significantly smaller than 155/80R17, increasing the mismatch in rolling circumference.

This positioning means the 155/80R17 reduces drivetrain compensation relative to compact spares, even though it still does not fully match most standard tire diameters.

155/80R17 Size Quick Specs

• Approved rim width range: 4.0–5.5"
• Typical inflation pressure: ≈60 PSI
• Overall diameter: ≈ 26.8"
• Section width: 155 mm 
• Sidewall height: 124 mm 
• Fits: 17-inch wheels (temporary spare applications)

Note: Calculated diameter is 26.76 inches. Actual mounted values may vary slightly (≈ ±0.1-0.2") depending on tire construction.

155/80R17 Dimensions in Inches

The 155/80R17 tire is approximately 6.1 inches wide, 26.8 inches tall overall, with a sidewall height of ≈ 4.9 inches. At this diameter, the rolling circumference is ≈84.1 inches, which determines the distance traveled per wheel rotation.

155/80R17 in Inches: All Measurements

• Overall diameter: ≈ 26.8"
• Width: ≈ 6.1"
• Sidewall height: ≈ 4.9"
• Wheel diameter: 17"
• Circumference: ≈ 84.1"

155/80R17 Circumference Difference vs Full-Size Tires

With a circumference of ≈84.1 inches, the 155/80R17 spare is closer to many standard 17-inch tire sizes, which typically range between ≈82 and 90 inches.

This results in a rotational difference of approximately -2.1 to +5.9 inches per revolution, or about ≈2.5% smaller to ≈7.0% larger, depending on the original tire size.

Because the 155/80R17 has a larger diameter than lower-profile spares like 155/70R17, the mismatch in rotational speed is reduced. This lowers the amount of continuous compensation required from drivetrain components during temporary use.

Axle Placement Requirements for 155/80R17

The 155/80R17 spare should be installed on a non-driven axle whenever possible.

• On front-wheel-drive vehicles, install 155/80R17 tire on the rear axle
• On rear-wheel-drive vehicles, install 155/80R17 tire on the front axle

Although its ≈26.8-inch diameter improves compatibility compared to smaller spares, the 155/80R17 tire size still differs from the original tire size. When mounted on a drive axle, this difference forces continuous differential adjustment.

Positioning the 155/80R17 spare on a non-driven axle reduces mechanical load and limits unnecessary drivetrain stress during temporary operation.

155/80R17 Inflation Pressure Requirements

A 155/80R17 temporary spare typically operates at approximately 60 PSI.

Even though the 155/80R17 taller sidewall increases air volume and contact patch length compared to lower-profile spares, load capacity remains dependent on maintaining the specified pressure.

If the 155/80R17 tire inflation drops below the required level, the sidewall flex increases beyond its intended range. This leads to heat accumulation and accelerates structural degradation.

Maintaining the correct pressure is therefore essential to preserve load support and prevent failure during temporary use.

Most Recommended 155/80R17 Tires

Best tires in 155/80R17 size include: Falken FK-090, Falken Temporary Spare