[Bill14564]

Originally Posted by tophcfa

No, valve stems can leak air very slowly if they are not tightened down properly. There is a rubber gasket in the stem that needs to be compressed to hold in air. Over time the stems can loosen and require being snugged down, typically only about 1/4/ to 1/2 turn. Sometimes the rubber gasket in very old valve stems can corrode and the valve stem needs to be replaced. A valve stem wrench can be purchased at any auto parts store, or in the automotive department of a box store, for less than $5. A package of replacement valve steams can be purchased on Amazon for under $10.

Correct me if I am wrong but the valve stem is a 1" to 2" piece of rubber and metal that is inserted into the rim from the inside of the tire. It's purpose is to allow the tire to be filled with air through the use of a valve within the stem. There is usually a valve stem cap that screws onto the outer end of the valve stem to keep dirt out of the valve. In newer vehicles the valve stem frequently contains the sensor for the tire pressure monitoring system (TPMS). In all cases that I am aware of, the valve stem is replaced from inside the rim meaning the tire must be at least partially removed from the rim itself. The hollow rubber/metal valve stems can be fairly inexpensive but I know those that contain the TPMS sensor cost more than $10 each.

Perhaps you are referring to the valve itself which is within the stem. Those can be removed and replaced. In all the years I have owned vehicles (cars, trucks, motorcycles, bicycles, lawn tractors, golf carts, wheelbarrows, boat trailers, etc) I have experienced a bad valve only one time. Maybe I've been luck and it happens more often than that. I have never needed a replacement valve (I had the entire stem replaced that one time) but it's good to know they are available.