Tires have information on the sidewall, what number tells you how tall the tire is or how wide the tire is ?

Question

I have N50-15's on the rear, and F70-15 on the front, my friend has P205/40R17 which numbers denote how tall the tire is, and how wide the tire is? Please break it down so I can understand P205= ??? /40= ??? and I know the 17 is the size of the rim. On my car 70's on the front, they are narrow, on the back are the 50's they are 10.5in wide....if you dont know, pass this one up.

Answer 1

P=speed rating, 205 is the height of the sidewall, 40 is the width of the tire, rim size is the last number.

Answer 2

P205/40R17. P means the max speed the tires can witheld, 205 is the width of the tire, 40 is the height of the tyre, R17 means it's only for Rims with size of 17 inch.

Answer 3

easy formula from a tire salesman

P=passenger
LT=light truck

your tires are very old the industry has not used N or F in a long time.

first three numbers is the width example 205 is 205mm
second number is height in relation to width example 40 is 40% of 205mm
the last number is the rim size example 17= 17 inch rims

so formula is width/height in relation to width R rim size

also you can see how old a tire is from the dot # the last four numbers is the week and year the tire is made for example 1003= 10th week of 2003 or for older tires 107= 10th week of 97
so to answer your question no your friends 17 inch tires will not fit on your 15 inch rims

Answer 4

P205/40 denotes the size and width and the terrific variety is the wheel length. P205 tells top i imagine and the 40 has to do with width of the tire. you've a 70 sequence at the front of your truck and 50 sequence on the rear. The 70 sequence is a thinner tire and the 50 is wider, am I properly?

Answer 5

"P" designates passenger tire
205 is the width of the tire in milimeters
40 is the aspect ratio...the height of the tire as a percent of the width...205x0.40=82 mm high.
"R" designates as a radial, as compaired to a bias tire
17 is the diameter of the rim in inches.

I'm not sure about the sizes you give for your tires.

Edit:
if the "R" is preceded by another letter, ie S,T,H or Z that would be a speed rating. the letter P is not speed, but for passenger as compaired to LT for light truck.

Answer 6

I told you when you asked it ten minutes before this one dude !