Your original post said 325-13.50-18, which is not a correct size. That is why I questioned it. It would have to be something like 325-65-18 (like you posted above). A 325/65/18 is a larger tire typically than a 35/12.50/18. A 325/65/18 is going measure close to 35" tall and roughly 13" wide. A true 35/12.50/18 is going to measure just that. Roughly 35" tall and 12.5" wide (unless it's Nitto and their Trail Grappler). Metric always seems to throw people off a little bit. Once you get it down, you'll understand that aspect of tire sizing more.
Rim width has everything to do with tire sizing. If you have a 9" wide wheel, you don't typically want to put a 13-14" wide tire on it. You can, but it's not what the tire was made for. You will see when looking at tire specifications that there is an ideal rim width to the right of the tire size. It is different for every tire. Most 305's are ideal on a 9-10" wide wheel, but you could get away with running it on a 8-8.5" wide wheel. When you run a wider tire on a narrower wheel, the issue at hand is going to be how much of the tire surface is actually touching the ground going down the road. If the tire is too wide for the wheel, you are going to have less tire on the road and the tire will not wear evenly....which can cause more issues than you think.
Hopefully I haven't rambled too much and you kind of get the idea.
Thanks for all the details. I get that it was not written correctly. Essentially all I was trying to figure out is how will the two tires compare width wise, so I tried to "translate" the metric one to match the Toyo somewhat. Even though the ProComp is a metric tire, it had details listing it as a 13.5 width tire, so I wanted to know if it will measure a true 13.5 like the Toyo will measure a true 12.5. And if that is the case, is there really that much of a noticeable difference between a 12.5 and a 13.5 tire. Probably bad wording on my part with the initial question.
So when you say that the ProComp will measure roughly 13" wide, in your opinion, do you think there would be a noticeable difference between that and the Toyo M/T? Will the Toyo measure a true 12.5?
And as far as the rim width, I already have the ProComps on my truck already and they wear perfect, so I'm not worried about either tire going on my wheels, but I get what you are saying. Just kind of had the itch to try something different.
No rambling at all, thanks again for taking the time to write it all out, much appreciated!
I would say its a noticable difference, not much but certainly noticable when its your truck. I must say I am much happier overall with the toyo's than the nittos, only got 40k out of the nittos and I am over 40k now on the toyo's and they have tons of life left in them. Plus I have gotten way more comments on the truck since the tire change.
Also my rims are 18x9 the width will effect how much bulge the tires have, the 325's had a good bit of bulge to them but never wore funny
Doesn't seem all that noticable in any pics but maybe these will help you out decide...
Best I can seem to do for pics
Thanks Josh. The Toyo does seem a little more narrow, but I like the tread pattern on it a lot more. Really gives the truck a different look.
