picked up a 6" railway spike a couple weeks back gaping hole 1/4" or bigger, tire went flat instantly. put 2 plugs in it & a can of tire slime pumped it back up & been good ever sinceOne thing to remember, the sealant (whatever brand you buy they are all about the same) is distributed by centrifugal force, so you are not likely to get much coverage on the side walls. Also, on 8-ply tires, the sidewalls are still the most susceptible part to a tear or puncture, and the hardest to patch.