If you find side to side or front to back between the stub axel housing and the bottom of the kingpin, this is usually the problem. These will need reamed to fit your kingpins. Not all kingpins are the same diameter. We have the ability to replace and ream them for you if you want to send your stub axels to us. If doing that, it's probably best to either get new kingpins from us or send us the kingpins you're planning to use. We also carry the upper bushing.