I'm looking to upgrade both my wheels and tires. I would like to take my old 17" front and 18" rears off and jump up to 18" front and 19" rears.
My question is, what do the different tire sizes mean?
Ex; Fronts, 265/30/18

What does the 265 mean?
What does the 30 mean?

I'm pretty sure I understand what the 18 means.

I just want a wider tire to look meaner...does that mean the 265 or 30?
I apologize if this is confusing, I'm dizzy over it myself

 

the first number is how wide it is......the second is how tall....and the third is how big......so the bigger the 1st # the wider the tire......the smaller the second.......the lower profile the tire is....and of course 3rd is the rim size....hope that explains it.....ps i have 18-19 combo.....very nice

 

Just be sure that when you get a set of tires, you ensure that the stagger between front and rear is maintained.

 

Thank you.

 

The 265 is the tire width, 265 millimeters
The 30 is the aspect ratio. 30 indicates the sidewall height is 30% of the tire width.

 

Information coutesy of....

http://www.discounttire.com/dtcs/infoHome.dos


Reading the Tire Size
The graphic shows what each letter and number in the size of a tire indicates. In this example, the tire size is P205/65 R15. The other items on the tire's sidewall have further explanations and have links at the bottom of this page.
Image of the Tire's Sidewall
P
Passenger car tire. If there is no P before the size it would indicate it is a European metric tire. An LT before the size would designate a light truck tire.

205
This is the Section Width in millimeters. This measurement is taken from sidewall to sidewall.

65
This number refers to the height of the sidewall, or the Aspect Ratio. It is a percentage of the section width. In this example, you would take 65 percent of 205 millimeters and this would give you the sidewall height.

R
Radial tire construction.

15
Wheel diameter in inches.

H
A tire receives its speed rating by the U.S. Government through meeting minimum standards for reaching and sustaining a specified speed. What does that mean to you? Well, in general, a higher speed rating will result in better car handling.

Two important notes when considering speed rating:
• We do not recommend downgrading the speed rating of your tires. This may result in poor handling and unpredictable steering. However, if you want better cornering response, there is no problem installing a higher speed rated tire on your vehicle.

• Never mix and match tires with different speed ratings on your vehicle. This will cause serious problems with the handling of your vehicle.

Below is a list of speed ratings along with the corresponding speeds they represent. Remember, the speeds are test speeds, not recommended speeds.



Q- Up to 100mph
R- Up to 106mph
S- Up to 112mph
T- Up to 118mph U- Up to 124mph
H- Up to 130mph
V- Up to 149mph W- Up to 168mph
Y- Up to 186mph
Z- 149mph and over

Additional Tire Size Information
The tire size displayed on this website may include these abbreviations:

At the end of the tire size:
OWL - Outlined White Letters
RWL - Raised White Letters
RBL - Raised Black Letters
ORWL - Outlined Raised White Letters
W, WW, WSW - Whitewall, White Side Wall
B, BLK, BW, BSW - Blackwall, Black Side Wall
BSL - Black Serrated Letters
VSB - Vertical Serrated Band
XNW - Extra Narrow White Width
XL - Extra Load
REIN - Reinforced
C - C load range for LT designated tires
E - E load range for LT designated tires

Additional Sidewall Information
• Treadwear, Traction and Temperature
• Air Pressure
• Ply Construction

 

Awesome !!!! Thank you for that graph chart.