Your question is beyond my expertise but I can share my thoughts. It would seem to me if the integrity of the kingpin is sound, the hitch jaws lock and release, and you experience no adverse chucking etc., a 1/8 should not matter. Something must have hit it so I would look carefully at the connecting members.
Best Wishes!
2001 Alpenlite 35RK
2007.5 Chev LMM Duramax/Allison
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2010 FLHTC Electra Glide Classic Red Hot Sunglo 🙂