I have had a slow leak on my F 150 for several weeks now. I have just been very busy and kinda put off getting it fixed, just goes visibly low in about a week. Well I took it in to get it plugged today at the local WalMart and the guy says he cannot plug it unless the hole is in the middle three treads. I have plugged tires and had tires plugged many times and I thought as long as it was not sidewall it could be plugged. Is he lying or am I just too cynical. It is two treads in from the sidewall clearly on the tread part of the tire.