hello , i had a friend of mine look at my straight axle loose kingpin on my 1939 chevy truck after new bushings were replaced . he noticed the kingpin lock bolt shaft was to long , sticking out the other side hitting the back side of the wheel stop . this caused the kingpin lock bolt not to tighten up correctly , leaving the kingpin loose . he made a small counter sink in the back side of the wheel stop enough to clear the extended locking pin bolt . this tightened the kingpin right up .

amazing what a second set of eyes can see and made a simple fix . hope this helps anyone . 1pete1