On my wifes truck (2005 F-150 supercrew), the two back tires so far have been patched due to a screw and a roofing tack causing a leak in them. This afternoon when I came in from work I noticed the passenger front tire was flat. Will it be safe to patch this tire and keep driving or would I be better off to replace the tires being that 3 of them now have had to be repaired? This vehicle carries my wife and 3 year old little girl on a daily basis, mostly short trips but the occasional few hundred mile trip. The tires are General AmeriTracs with about 50% tred left on them. Thanks for any opinions.