I use the old wood hauling P-U for everything. So, recently when shopping for replacement tires I found the local tire suppliers had only "P" series tires available. I do know that Firestone makes a commercial grade tire "TRANSFORCE" but the local Firestone store tells me it is unavailable. I did find this tire at "tirebuyer.com" at a quite favorable price. Good reviews. Has anyone else looked at the tires when you fully load your truck with wood? I put extra pressure in them with such a load. But, "P" series tires are not made for the potentially heavy load of logs. I also get better service life from the more beefy tire. I am interested in your experience.