Hi Scotty 101st ABN vet here. How do I know when a nail puncture can be repaired vs replacing the tire? The puncture is on the Tire Seam - between the sidewall & the tread.
if it's outside of the steel belt then you're risking separation, but take it to a tire shop and see
i think some places do not patch if on sidewall. If patching it yourself, then what the heck. I plug mine but make sure I have a good solid spare, just in case.
I also make sure I have a good, full size, spare tire. Those little 50Mile spares are the first thing to be replaced when I buy a car. I found it crazy to have cars with airbags up the ying-yang and no real spare tire.
I have a friend that owned a tire shop for over 50 years. He told me that the reason most places won't patch close to the sidewall is because of a multi- million dollar lawsuit that a shop in California lost when a tire they patched failed and a fatal wreck occurred. My friend continued to patch pretty much anywhere on a tire, said he hadn't had any problems and had been doing it for decades.