Two weeks after installation, our 30-foot trailer pulled with its tandem. He was driving at 65 mph and received an alert that the truck's left front tire was rapidly losing air. As I looked for a place to stop, the pressure dropped from 80psi to 70, then 60, then 50 and 40. I stopped at the shoulder, it was lost and uneven. Not the best place to change a wheel. The pressure drop slowed dramatically, so I hobbled down the road to the country store. The valve stem leaked when inserted into the…