Valve Stem Replacement

Have a feeling I know the answer to this but; my backhoe is leaking air around the stem, the core is fine. It looks like the one in the pic except instead of a nut on the bottom, it is round and knurled like the middle and top. Tried grabbing the middle and the bottom with pliers and it springs back (rubber seal). Any tricks or does the wheel need to be broken down to replace?



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Valve Stem Replacement