Glossary
Valve core
The small spring-loaded pin inside the valve stem that controls airflow. The valve core seals when not in use and opens when pressed by a gauge, inflator, or cap. A deteriorated valve core is one of the most common causes of slow pressure loss in truck tires. Valve cores are inexpensive and replaceable without removing the tire.
Real-World Use
A drive tire consistently 8 PSI low is tested with soapy water at the valve tip, producing bubbles — the core is replaced and the tire holds pressure for the first time in weeks.
What to Pair It With
Read this term with the full tire sidewall, vehicle rating information, manufacturer documentation, and the actual condition of the tire.
This site is for general information only. It does not replace professional tire service, DOT compliance advice, tire manufacturer instructions, vehicle manufacturer recommendations, or fleet policy.