3 days after installation, both right tires turned red and our air level dropped significantly. I thought my wife hit something on the right side so I had it towed to my mechanic for repair. I felt good, they told me there was a problem and they would take care of my wife's safety. I thought so lol. The mechanic looked at the whole tire and couldn't find any leaks. Finally he sprayed his leak detector on the valve cover. It went like crazy. The valve covers themselves caused the leak. They were tight, but the rubber seal just wasn't that good. They leaked and caused negative pressure. A device designed to alert me to a printing problem caused the problem. The mechanic refilled the tires without these caps and we haven't had any problems since.