Comparison

245/35 R19 vs 255/40 R17

255/40 R17 drops the rim from 19 to 17 inches versus 245/35 R19, trading wheel size for taller sidewall. This setup moves rolling diameter a touch off the original spec. The speedometer offset is small but measurable; worth keeping in mind if you watch the dash closely. More sidewall typically improves comfort and curb protection, especially on city streets. Diameter change stays inside the conservative ±3% safety window — an OEM-safe fitment on most vehicles.

TakeTypical choice for a dedicated winter or off-road setup where extra sidewall pays off.

Quick math: 255/40 R17 is 18.3 mm shorter than 245/35 R19, shifting the speedometer by -2.80%.

Current Tire

245/35R19

New Tire

255/40R17
245/35 R19
255/40 R17

Ground line · scaled comparison

Excellent Fit

Within ±3% — safe for daily driving

Diameter change

-18.3 mm

-2.80%

Speedometer at 100

97.2 km/h

-2.80% error

Ground clearance

-9.1 mm

ride height delta

Sidewall change

+16.3 mm

revs/km: 500.6

Permalink for this comparison:

/compare/245-35-r19-vs-255-40-r17

Detailed comparison

Metric245/35 R19255/40 R17Difference
Overall diameter654.1 mm635.8 mm-18.3 mm (-2.80%)
Sidewall height85.8 mm102.0 mm+16.3 mm
Circumference2.055 m1.997 m-57.5 mm
Revs / km486.6500.6+14.0
Ground clearancereference-9.1 mm-9.1 mm
Speedometer @ 100 km/h100.0 km/h97.2 km/h-2.80 km/h

Verdict: excellent

Within ±3% — speedometer, ABS and traction control should behave normally.

Speedometer impact

At a true 100 km/h, your dashboard will read 97.2 km/h after switching to 255/40 R17 — a -2.80% offset. Use the speedometer error calculator to recheck for other indicated speeds, and the speedometer error guide for the full background.

Ground clearance change

The new tire's half-diameter changes ride height by -9.1 mm. Small differences are absorbed by suspension travel, but anything beyond ±10 mm can affect headlight aim, fender clearance and bump-stop margin. See the plus-sizing guide before committing.

Back to

245/35 R19

Back to

255/40 R17

Drivers also compare

Closely-related fitments and plus-size swaps for 245/35 R19 and 255/40 R17.

Related topics

Frequently asked questions