285/70R17 vs 285/75R17

285/75R17 is 1.12 inches (3.4%) taller than 285/70R17 and 0.00 inches wider. Here are both sizes side by side, drawn to scale.

Last updated · Calculated from the sidewall code · Sources

Tire sizes

Type it as it appears on the sidewall: 275/60R20, LT265/70R17 or 33x12.50R20.

Difference in height
+1.12″
285/75R17 vs 285/70R17
285/70R17285/75R17Difference
Overall diameter32.7″ 831 mm33.8″ 859 mm+1.12″ (+3.4%)
Section width11.2″ 285 mm11.2″ 285 mm±0.00″
Sidewall height7.85″ 200 mm8.42″ 214 mm+0.56″
Wheel (rim) diameter17″17″same
Circumference102.8″ 2610 mm106.3″ 2700 mm+3.5″
Revolutions per mile617596−20
Ground clearance+0.56″
285/70R1732.7″ × 11.2″32.7″285/75R1733.8″ × 11.2″33.8″
Drawn to scale: side view and tread width.

285/75R17 is 1.12″ taller (3.4%) and 0.00″ wider than 285/70R17. With a speedometer set up for 285/70R17, an indicated 60 mph is really 62.1 mph on 285/75R17, so the gauge reads 3.4% low. Ground clearance at the axle changes by +0.56″.

A 3.4% difference is more than the ±3% shops commonly use as a limit: plan to recalibrate the speedometer, check clearance (and lift or leveling needs), and consider regearing if it's a big jump.

Speedometer showsReal speed on 285/75R17
30 mph31.0 mph
45 mph46.5 mph
60 mph62.1 mph
70 mph72.4 mph
80 mph82.7 mph

What changes when you switch to 285/75R17

Sizes are theoretical, from the sidewall code. The same size can differ by a few tenths of an inch between brands and tread patterns; check the maker’s spec sheet for the exact model.

Other comparisons

Frequently asked questions

How much bigger is 285/75R17 than 285/70R17?

285/75R17 is 1.12 inches (3.4%) taller and 0.00 inches wider: 33.8" × 11.2" versus 32.7" × 11.2".

Will 285/75R17 change my speedometer?

Yes, by 3.4%. Going from 285/70R17 to 285/75R17, an indicated 60 mph is about 62.1 mph.

Can I replace 285/70R17 with 285/75R17?

Possibly, but the height difference is over 3%, so check clearance and plan to recalibrate the speedometer. Both fit a 17" wheel; confirm the rim width, load index and clearance for your vehicle.

Do I need to regear going from 285/70R17 to 285/75R17?

Usually not for a 3.4% change. With 3.73 gears, the 285/75R17 acts like 3.61.

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