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Tire size

275/55R20 tire size: dimensions explained

Factory size on the Ram 1500. Below are the dimensions calculated from the size marking itself. Your vehicle's correct size, load index and speed rating are on the placard in the driver's door jamb; check it before buying.

MeasurementMetricImperial
Section width275 mm10.83 in
Sidewall height151.3 mm5.95 in
Overall diameter810.5 mm31.91 in
Wheel diameter508.0 mm20 in
Circumference2545 mm100.2 in
Revolutions per mile632

Calculated values: diameter = wheel + 2 × (width × aspect ratio). Real tires vary slightly by brand and model.

Reading the marking

275 is the section width in millimetres, 55 is the sidewall height as a percentage of that width, R means radial construction, and 20 is the wheel diameter in inches. A passenger (P or Euro-metric) tire and an LT tire in the same size are not interchangeable without checking load requirements.

Compare 275/55R20 with another size →

275/55R20 tires at Tire Rack

All-season

TireLoad/speedPrice per tire
Advanta HPZ-02
Ultra High Performance All-Season		XL 117V$160.08View at Tire Rack
Radar All Season GT
Grand Touring All-Season		XL 117V$168.25View at Tire Rack

Highway / touring

TireLoad/speedPrice per tire
Advanta SVT Plus
Crossover/SUV Touring All-Season		XL 117T$161.97View at Tire Rack
Advanta HTR-800
Highway All-Season		XL 117T$162.46View at Tire Rack

All-terrain

TireLoad/speedPrice per tire
Advanta ATX-850
Off-Road All-Terrain Truck		113S$181.60View at Tire Rack
Radar Renegade A/T
On-Road All-Terrain		XL 117H$182.00View at Tire Rack

Winter

TireLoad/speedPrice per tire
Goodyear WinterCommand (SUV)
Light Truck/SUV Studdable Snow Truck		113S$170.93View at Tire Rack
Continental VikingContact 7
Studless Ice & Snow		XL 117T$223.27View at Tire Rack

Rugged / mud-terrain

TireLoad/speedPrice per tire
Radar Renegade R/T
Rugged All-Terrain		XL 117T$221.25View at Tire Rack
Radar Renegade R/T
Rugged All-Terrain		E 120/117Q$240.83View at Tire Rack

Showing the lowest-priced in-stock options in each category from 146 275/55R20 tires in Tire Rack's feed, sorted by price only. We don't rank by commission. Match or exceed the load index and speed rating on your placard.

Affiliate links: if you buy through a Tire Rack link, RightTread may earn a commission through CJ. It doesn't change your price. Prices are Tire Rack's per-tire prices from Tire Rack's product feed as of Nov 7, 2026, 9:19 PM PT. Prices change, so confirm on Tire Rack before you buy. Disclosure

Other sizes