The 295 is the section width, not the tread width. See this quote from Tire Rack:
"Section Width
Following the letter(s) that identify the type of vehicle and/or type of service for which the tire was designed, the three-digit numeric portion identifies the tire's "Section Width" (cross section) in millimeters.
P225/50R16 91S
The 225 indicates this tire is 225 millimeters across from the widest point of its outer sidewall to the widest point of its inner sidewall when mounted and measured on a specified width wheel. This measurement is also referred to as the tire's section width. Because many people think of measurements in inches, the 225mm can be converted to inches by dividing the section width in millimeters by 25.4 (the number of millimeters per inch).
225mm / 25.4 = 8.86" "
Standard terminology helps us all talk about the same thing.
Slicks are another system entirely.
R.
I measured mine with 2 squares and a tape measure
pretty simple... I had to send my 295/65 back due
to the height.. just too close
EDIT
from Summit
Tire Size: 295/55-15
Wheel Diameter: 15 in.
Sidewall Style: Blackwall
Tire Construction: Radial
Tire Diameter: 27.80 in.
Tire Diameter Range: 27-27.99 in.
Section Width: 12.20 in.
Tread Width: 10.60 in.
Minimum Recommended Wheel Width: 8.00 in.
Maximum Recommended Wheel Width: 10.50 in.
