King pins are often replaced without checking that the pins are a tight fit in the I beam. It is not uncommon for the eye in the I beam where the king pin goes through to become worn. When assembled, even with a new pin, it makes it feel like the pins are worn and loose when it is movement between the pin and I beam you are feeling.
The I beams can be bored and bushed$$$ or a replacement axle will need to be found.
If all is in good shape and lubed regularly king pins will last a very long Time.


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