It's about $15 a tire. A couple of dollars less if you have it done when you first buy the tires. I had it done when they mounted my Toyo M/Ts, so don't know the difference it made, but they handle excellent in the rain on curves. Here's a couple of pics of the sipes on mine.TravisDTD said:Some places can sipe them for you to make them better in the snow. I think les swab does it and Discount tire/ Americas tire does too. My dad just had his long Trail BFG's done at a Discount Tire in Oregon and he said it helped quite a bit. I can't remember how much he said he paid.