I've seen some of the tire calculators online, but none of them seem to give a camparison between standard and metric tires. My FX4 came with 275 65 18 tires, and it now has 32 12.5 17 tires on it. I want to see what the difference is. I am looking to get new tires that are a bit closer to stock size since I'm doing a lot of towing now. Any help, links would be much appreciated.

 

I don't know of a chart, but I can explain to you how to convert a metric size to standard. I'll use your 275/65-18 as an example. The first number (275) is the width of the tire in mm. The second number (65) is the aspect ratio or percentage of the tire's width that it is tall. The third number (18) is your rim size. Start with 275mm and convert that to inches (275/10=27.5cm/2.54=10.8inches wide). Then you figure out what 65% of that is (10.8*0.65= 7 in.) Then you double that and add your rim size (7*2=14+18=32 inches). So therefore your 275/65-18 is about equivilant to a 32x10.50- 18 tire. I hope all that made sense.

 

www.redrock4x4.com/tech/tire_calc.php

 

hope this helps