Skip to content
Sidewall

305/35R18

305 mm across the tread, a sidewall 35% of that — 107 mm — on a 18-inch rim. That puts the whole wheel at 26.4 inches tall.

107 mm sidewall671 mm · 26.4"
Sidewall
4.20"
107 mm
Overall
26.4"
670.7 mm
Circumference
83.0"
2.107 m
Revs per mile
764
per minute at 60 mph

What it needs to sit on

i

It mounts on a rim between 8.5" and 11" wide, and the tread follows the rim: roughly 5 mm of section width for every half-inch, so about 293 mm across at the narrow end and 318 mm at the wide one. Written the way lift kits and wheel wells are, it is a 26.4×12.0R18 — tall by wide, in inches.

What goes wrong on this size

i

2 drivers have filed a complaint. 0 of them ended in a crash, and nobody was hurt. Nobody died.

2 of them name what let go, and it is most often tread separation. Avon is named more than any other brand.

What let goComplaints
tread separation2

Where the wheel is named, 2 of 2 were on the rear, and 0 on the front.

What fits instead

i

Same 18-inch rim, height within 3%. Past that the speedometer starts lying and things begin to rub.


SizeHeightRide heightSpeedo reads 60, you doCompare
295/35R1826.1" -1.0 %-3.5 mm59.4 mphside by side
315/35R1826.7" +1.0 %+3.5 mm60.6 mphside by side
285/35R1825.9" -2.1 %-7.0 mm58.7 mphside by side
325/35R1827.0" +2.1 %+7.0 mm61.3 mphside by side
285/40R1827.0" +2.2 %+7.3 mm61.3 mphside by side
325/30R1825.7" -2.8 %-9.3 mm58.3 mphside by side

Same height, different rim

Bigger rim, same overall height. Sharper steering, harsher ride, and far less rubber between your wheel and the next pothole.


315/30R1995 mm sidewall — 11% less
295/40R17118 mm sidewall — 11% more
275/35R1996 mm sidewall — 10% less
335/35R17117 mm sidewall — 10% more
305/40R17122 mm sidewall — 14% more
305/30R1992 mm sidewall — 14% less

If you fit something taller

A taller tire covers more ground per turn, so the needle reads low and the odometer counts short. Over ten thousand miles on the dial, the last column is what you really drove.


Fitted insteadReads 30Reads 50Reads 70Real miles per 10,000 shown
295/35R1829.7 mph49.5 mph69.3 mph9,896
315/35R1830.3 mph50.5 mph70.7 mph10,104
285/35R1829.4 mph49.0 mph68.5 mph9,791
325/35R1830.6 mph51.0 mph71.5 mph10,209
285/40R1830.6 mph51.1 mph71.5 mph10,216