CarSpecsHQ

245/35R21 vs 295/35R21

295/35R21 is outside the ±3% rule as a replacement for 245/35R21: the diameter differs by +4.97%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

21" rim
245/35R21 27.75" · 295/35R21 29.13" · drawn to scale

Side by side

245/35R21295/35R21Difference
Overall diameter27.75"29.13"+1.38" (+4.97%)
Section width245 mm295 mm+50 mm
Sidewall3.38"4.06"+0.69"
Rim21"21"same
Circumference87.2"91.5"+4.3"
Revs per mile727692-34
Ride height——+0.69"
Speedometer reads 60 mph60.063.0+3.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 63.0 mph

With 295/35R21 on a car calibrated for 245/35R21, the speedometer reads 57.2 mph when you're really doing 60, and the odometer under-counts by 5.0%.

Speedo showsActual speed
30 mph31.5 mph
45 mph47.2 mph
60 mph63.0 mph
70 mph73.5 mph
80 mph84.0 mph

Other sizes close to 245/35R21

Questions

Can I replace 245/35R21 with 295/35R21?

295/35R21 is outside the ±3% rule as a replacement for 245/35R21: the diameter differs by +4.97%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 245/35R21 and 295/35R21?

295/35R21 is 1.38" taller and 50 mm wider; the sidewall is +0.69". At an indicated 60 mph you'd actually be doing 63.0 mph.

Will 295/35R21 fit on 245/35R21 wheels?

Both use a 21" rim, so the wheel diameter matches; check the wheel's width range for a 295 mm tire and the fender clearance.