Originally Posted by slupie
No offense but this statement is funny "Their impact guns are calibrated to not over torque it" can not calibrate an impact gun, too many variables , one is psi input into the gun and the other impacts per minute. Even torque wrenches when calibrated they are +\- certain percentage depending on brand and quality.
Torque sticks are not that accurate either, gun variables like how many impacts per minute it is set to and input psi.
Never use impact gun to install wheel lugs. The reason is uneven torquing of the lugs that could possibly warp the rotor hat causing vibrations during braking. Over-torqued lugs cause a problem for the owner if one gets a flat and the nuts can not be loosened with a tire iron on the side of the road. Others are stripped studs, cross thread and possibly others.
Theres torque level settings built into them, using them daily for a living they know how much is too little and to much by feel/sound. I worked at the benz dealer ship for a while just out of school. Just about every tech in there laughed at me when i first started and torqued each nut with a wrench.
Keep in mind these guys flag hours and the last thing on their minds is to take time on your nuts. The also make torque sticks (impact gun) for noobs that you often see use them at americas tires. With that said, if im at a shop and i see an unknown impact ft-lb ratings @ X psi i would never use it on my own wheels. Just lightly zip them down and torque by hand. I have my own gun and know its feel/sound.