I've got a leak on my truck tire - about 1 PSI every couple of days. I got tired of adding air every 10-14 days, so took it to my little podunk tire shop, where the guy said he couldn't find any leak.
Nevertheless it's leaking. I'm guessing I got a thorn through the tire from limbing a few of these damn Russian olive trees I have. I was hauling branches from along my road to my burn pile, and I'm betting one of those nasty thorns pierced the tire. Any tips for trying to find the leak (whether it's from the thorn or not) that the tire shop wouldn't have already used?