Yes, absolutely, set tire pressure at recommeded pressure. If the pressure recommended is, say, 26 psi, set it for 28, don't let it go below 25, rather than set it for 26, and letting it go as low as 23 before refilling. The higher the pressure, the better the gas milelege, but go too high and you reduce traction -- a dangerous situation. 3 psi over the recommended pressure is generally not considred dangerous. However, and this is very important: do not check your tire pressure after you have been driving for an hour, and the tires have warmed up. Check the pressure before driving, or after only driving for 5 or 10 minutes. Cold. Prolonged driving will bring the pressure up as much as 3 psi. So if the nominal pressure is 26, and you set it to 26 when the tire is hot, you will be setting it to 23 cold -- 3 psi too low. Don't try to estimate how hot the tire is. Just set it when it is cold. In really freezing weather, like 0 degrees F, the pressure will go down a pound or 2 -- so if you set the pressure to 26 then, the actual pressure at "normal" cold will be 27 or 28. Slightly too high. In really frigid weather, drive a few minute before setting the pressure, and set it a pound or so low anyway if there is snow or ice on the ground, to improve traction. Safety is more important than getting good gas mileage. In other words, drive 10 minutes, and set the pressure to 25 instead of 26.
Drivers manuals will tell you that 26 means 23 to 29. But mild or hot weather you can easily keep it 25 to 28, without needing to check it excessively frequently.
Don't repair tubeless radial tires with a plug. "Break" at least one bead and patch it from inside. Plugs tend to interfere with the running-surface of the tire being able to stay flat on the road. There may be "umbrella" patches that don't leave anything in the hole you pushed them thru, to get to the inside of the tire, these may be ok, but the kind where you leave something in the hole, is not a good idea. But steel-belted radials tend to shred these as you push them thru, ruining their usefulness as a patch, so i still think the best thing is to break both beads, remove the tire from the rim entirely, and put the patch on from the inside. You can stick something thru the hole before removing the tire, so you know where it is once you get inside. But I don't find that necessry. Once I locate the leak by putting the tire in my bathtub, i then mark the outside of the tire across from where it is, and when I get the tire off, I can always eyeball the hole. They are easier to see from the inside than they are from the outside.
