King Pins replacement- in my 1951 3800.

[lmdangerous]

Seems that I have found my vibration problems at about 65 MPH and above.My king pins show a bit of slack. Not bad but more than they should- I am ashamed to say that I have run worse, just not at that speed.
Who has the best set out there and does anyone have any knowledge about using the nylon bushings verses the bronze??? Napa list them even the shackels etc, but I wanted to bounce it off of some that have been there done that?
thanks LMD

[Katrina/10]

I don't think worn king pins cause vibrations.

[mr48chev]

I'm rather inclined to go with what Katrina/10 said on the "vibration". Not that the kingpins are probably due for replacement but in that most likely the vibration is due to a balance problem with a Wheel and tire, hub and drum or drive shaft depending on where the vibration is originating.

The first thing I would do is make sure that my wheels were clean inside and out and that there was no accumulated mud or dirt on the inside of one of the wheels. If that doesn't cure the problem I would hunt down a shop that uses an on the vehicle spin balancer and have them spin the wheels on the truck. That is because sometimes you can have perfectly balanced wheels and tires and have a drum that is a bit out of balance. I have even seen hubcaps that were out of balance in a couple of cases but those were both on the same model of new Ford cars from the early 70's.

I've used the nylon bushings in the past and they are very simple and quick to install and work ok but on my truck they didn't seem to last all that long and after about 30K they needed replacing again. I've had much better luck with the metal bushings that have to be fitted to the pins after they are installed and have good clearances. That does call for a trip to the machine shop to have them fitted in most cases though. Greasing every thousand miles is a key to keeping them in good shape.

[diceman50]

I used needle bearings on my 58 Apache. Since I don't have power steering I was looking for something to reduce the steering effort, which it did. After approx. 10K they are working well.

[lmdangerous]

The vibration is similar to what I had years ago on a 56 that I had. The steering wheel gets pretty violent when it occurs.It does not occur all the time. I checked the bearings - they look good. Ajusted the steering box- it had very little slack and almost none when I got through. ( my luck in the past with these trucks is that the steering box is always worn out)The toe end /out was adjusted recently.I also checked the tierod ends and the drag link. The only measurable slack that I have is on the pass.side spindle in the king pin. Still I have driven worse - lots worse. I thought I looked at my tires but then again I have not done a soin balance. The wheels are clean also so thats where I am. thank for the info on the bushings - that tells me what i want to know about that . any other things to look at ??? speak up - you wont hurt my feeling - just want it fixed .
LMD

[lmdangerous]

Ok. New info. I jacked up the truck one side at a time and used my real long pry bar. The bottom of the pass. side king pin shows a fair amount of slack. Most at the bottom and it appears that the kingpin boss in the axle shows a fair amount as well. Guess I will be oversizing and reaming the axle ends. At least napa does offer a 10 and 20 over set. Time will tell. Funny that the driver side was not or did not appear to be worn at all. Weird lol.