Tire Size Calculator

Tire Size Finder (optional):

Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
155/85r18 vs 165/80r17 Tire Comparison Side By Side
  155/85-18 165/80-17 Difference
Diameter inches (mm) 28.37 (720.7) 27.39 (695.8) -0.98 (-24.9) -3.5%
Width inches (mm) 6.1 (155) 6.5 (165) 0.39 (10) 6.5%
Circum. inches (mm) 89.14 (2264.15) 86.06 (2185.92) -3.08 (-78.23) -3.5%
Sidewall Height inches (mm) 5.19 (131.75) 5.2 (132) 0.01 (0.25) 0.2%
Revolutions per mile (km) 710.8 (441.67) 736.23 (457.47) 25.44 (15.81) 3.6%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)19.31 mph (31.07 km/h)
25 mph (40.23 km/h)24.14 mph (38.84 km/h)
30 mph (48.28 km/h)28.96 mph (46.61 km/h)
35 mph (56.33 km/h)33.79 mph (54.38 km/h)
40 mph (64.37 km/h)38.62 mph (62.15 km/h)
45 mph (72.42 km/h)43.45 mph (69.92 km/h)
50 mph (80.47 km/h)48.27 mph (77.69 km/h)
55 mph (88.51 km/h)53.1 mph (85.46 km/h)
60 mph (96.56 km/h)57.93 mph (93.22 km/h)
65 mph (104.61 km/h)62.75 mph (100.99 km/h)
70 mph (112.65 km/h)67.58 mph (108.76 km/h)
75 mph (120.7 km/h)72.41 mph (116.53 km/h)
80 mph (128.75 km/h)77.24 mph (124.3 km/h)
85 mph (136.79 km/h)82.06 mph (132.07 km/h)
90 mph (144.84 km/h)86.89 mph (139.84 km/h)
95 mph (152.89 km/h)91.72 mph (147.61 km/h)
100 mph (160.93 km/h)96.55 mph (155.37 km/h)

Gear Ratio / RPMs for New Tire (@ 65 mph)
2.35 2.73 2.94 3.07 3.21 3.31 3.42 3.55 3.73 3.91 4.11 4.27 4.56 4.88 5.13 5.29 5.38 5.71 6.17 7.17
18742177234424482559263927272830297431173277340436363891409042184289455249195716
Better Fuel Economy Factory Ratios Increased Power

Most Popular 155/85-R18 Comparisons

To Top