Hello everyone, I'm looking for some feedback/advice on a king pin situation. A little bit about my truck: my AD 3100 per the title is a '48 but in actuality it sits on a 1950 or newer frame (has conventional front tube shocks); solid I-beam front axle and original replacement leaf springs and ride height; 327 V-8, 700R4, Camaro rear axle w 3.73 posi; front disc brakes/rear drums; front stabilizer; power steering w a Saginaw gear box from a 1973 1/2 PU; tires are Bridgestone P255/70R15 at all 4 corners. It was a $200 POS and over the past 42 years I think I've turned it into a pretty decent vehicle, doing all the work myself. One of the few things I've not yet addressed on this truck is the king pins. When I bought it from the prior owner he said he'd had the king pins replaced (see picture of upper king pin plug). The truck rides great although it handles like and old truck, which is ok with me. It was professionally aligned and goes perfectly straight down the road. It'll cruise all day long at 70mph. Gas mileage: not so good. My problem is wheel hop and tire wear (cupping) at the left front corner. The wheel hop starts at around 50mph, and gets worse up to about 55, and then diminishes and goes away at about 60. All of the tires were force balanced and rotating the tires makes no difference. But, I think I've isolated the problem. I have no perceptible side play on either front wheel, however, my up/down clearance (end play) at the left front between the axle and the steering knuckle is .025" (spec is .005). See picture of feeler gage. Right front clearance is .008" My question is: I'm inclined to believe the PO's claim that the king pins were replaced, considering the stake marks at the king pin plugs, however, how far would you go to correct my situation? My thought is that the mechanic who did the king pins so many years ago screwed up and/or didn't care about the end play. This truck with the old straight 6 never went much past 45mph so tire hop would never have been a complaint. I'm from the old school where "if it works don't fix it" so I'm inclined to not do a complete king pin replacement. Obviously I'm going to have to remove the left king pin to install the shims and I'll inspect the assembly further. Also, I'm in need of a set of shims to correct the end play: anyone out there want to sell me some left over shims from a king pin job or can anyone suggest where I can get ONLY the selective shims to fix the end play? Anyone else experienced wheel hop due to this excess clearance? Am I on the right track? Thanks Guys, Regards, Dave
