Ford pickup king pin difference

I've got to replace the king pins in my 60 pickup. I have an 53-56 drop beam in the truck and 60 spindles. What is the difference between the 53-56 kingpins and the 57-60 kingpins?

 

Generally speaking when swapping spindles to axles, the kingpins used belong to the spindles.

 

Judging by the pics found on a thread here: http://www.ford-trucks.com/forums/search.php?searchid=3493191 the earlier king pins appear to have a 'head' on the top where the 57-60 is necked down on both ends for an o-ring. I'm fairly certain they're smaller diameter than the 57-60s too.
Disclaimer: I've never touched a pre-58 ford axle but my 59 and 60 did NOT look like this picture.

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I'm not positive, but I think the diameter is the same on them.

So go with the 60 king pins then.

 

Anyone know for sure?

 

I would go with what was used for the spindles . I will assume the axel was reamed out to fit the spindles . Now this is just a guess . the only other thing is to get a king pin and mike them out to see what fits .

Retro Jim

 

The 60 spindles on a 53-56 axle with throw your camber way out. They are on different degree of angles. Not a good combo, it will wear your tires out quick..

 

Do you know what the degree of camber is on both of them?

 

Looks like both king pins are .859 dia.