School me about tire size. I have 235-85-16. I know what 16 means but which one is height and which is width? And also what does height and width do for you in terms of load, fuel economy, traction, handling?
235 is your tire width in milimeters, the 85 refers to the sidewall aspect ratio and it means the sidewall height is 85% of the tire width.
In any case - generally the larger the 3-digit number the wider the tire, wider tires make for more rolling resistance and thus increased fuel consumption. Also if we're comparing two tires of the same width but with different aspect ratios, say a 235/70-16 and a 235/85-16, the tire with a larger aspect ratio number (85 in our example) will have a taller sidewall, and since they both go on the same wheel the overall outside diameter of the tire will be larger.
Honestly I think this is a rather silly way of sizing tires, as these numbers really don't telly you much about the tire's actual dimensions - case in point the 235/85-16s that I have in the back of my truck are the exact same diameter as the 265/75-16s that live on the front axle, but you wouldn't know it for sure unless you actually measured them up - yeah, you'll know the fronts are wider than the rears, but that's about it really. On the other hand the 35x14.5x15 Bajas that were on my old mud-slinger made a whole lot more sense to me - 35" diameter, 14-1/2" wide, goes on 15" wheel - nice and simple.
And if you really wanna get lost and confused, there is the matter of load ratings - hell if I know how they determine these, but I know that if you look at two tires with load rating indicated by the same letter (say "D") the larger tire will generally have more load capacity in lbs - for instance 265/75-16D tires can haul more weight on them than 235/85-16D tires, and also more than say 215/85-16E tires. My current steer tires are 265/75-16E and are rated at like 3400 lbs each, my rears are of the 235/85-16E size but since they haven't arrived at the tire shop yet I can't tell you exact load capacity in lbs, I expect around 3000 when in SRW configuration (DRW setups are always a bit less than the SRW number, not sure exactly why tho).