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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
33/12.5r18 vs 305/65r18 Tire Comparison Side By Side
  33/12.5-18 305/65-18 Difference
Diameter inches (mm) 33.02 (838.8) 33.61 (853.7) 0.59 (14.9) 1.8%
Width inches (mm) 12.52 (318) 12.01 (305) -0.51 (-13) -4.1%
Circum. inches (mm) 103.75 (2635.17) 105.59 (2681.98) 1.84 (46.81) 1.8%
Sidewall Height inches (mm) 7.51 (190.8) 7.81 (198.25) 0.29 (7.45) 3.9%
Revolutions per mile (km) 610.72 (379.48) 600.06 (372.86) -10.66 (-6.62) -1.7%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)20.36 mph (32.76 km/h)
25 mph (40.23 km/h)25.44 mph (40.95 km/h)
30 mph (48.28 km/h)30.53 mph (49.14 km/h)
35 mph (56.33 km/h)35.62 mph (57.33 km/h)
40 mph (64.37 km/h)40.71 mph (65.52 km/h)
45 mph (72.42 km/h)45.8 mph (73.71 km/h)
50 mph (80.47 km/h)50.89 mph (81.9 km/h)
55 mph (88.51 km/h)55.98 mph (90.09 km/h)
60 mph (96.56 km/h)61.07 mph (98.28 km/h)
65 mph (104.61 km/h)66.15 mph (106.47 km/h)
70 mph (112.65 km/h)71.24 mph (114.66 km/h)
75 mph (120.7 km/h)76.33 mph (122.85 km/h)
80 mph (128.75 km/h)81.42 mph (131.03 km/h)
85 mph (136.79 km/h)86.51 mph (139.22 km/h)
90 mph (144.84 km/h)91.6 mph (147.41 km/h)
95 mph (152.89 km/h)96.69 mph (155.6 km/h)
100 mph (160.93 km/h)101.78 mph (163.79 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
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