I was adding air to the motorhome tires (I love my Viair air compressor!) and was turning and turning the valve stem cap when I realized the cap wasn’t coming off. The stem itself was unscrewing! I figured it out just in the nick of time before I unscrewed the stem all the way. I hurriedly turned it back in, held the stem and got the cap off and added air.
Having had a valve stem come out while on the road, I knew just how bad it could get. It was lucky that when the valve stem blew off it was on an inside dually and not the front steer tire.
We didn’t have a tire pressure monitoring system (TPMS) at the time and the six-month-old tire was completely destroyed. About $800 later, we had a new tire and a battle getting the money back for the defective mounting. Once our persistence on our claim got high enough in the pecking order, Freightliner sent us a check.
The valve stem unscrewing incident made me think about articles I had seen by tire expert Roger Marble on RVtravel.com about valve stems and a valve stem tightening tool. I checked with Roger, and he told me that over-tightening a valve core can cause it to fail, so it’s best to use the little valve core tool. The nut on bolt-in metal stems only needs 25 to 45 inch-pounds, so a basic “snug” with a regular hand wrench is fine. Here’s a link on Amazon to a valve core tool that Roger recommends. It’s also available at auto parts stores.