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1957 Chevrolet 5700 LCF. I have started the process of replacing the front axle king pins and bushings. GM Heritage site calls for the pin diameter of 1.109" and the bushings at 1.0975-1.1005". With these dimensions the pin would be tight in the bushings. The 1957 Shop Manual calls for the pin diameter of 1.109" and the bushings at 1.111", that seems to be too sloppy at .002" clearance. The eye in the axle is good so I'm using standard pins and bushings, whad'ya think, are they both wrong specs?

Her is a link from old gmc truck site never used this service just noticed it was on the site .Kevin

KEVINSKI,

Just a note that the info in that screen shot indicates a different king pin size than what 78buckshot has noted.

Thinking it indicates that is only size being offered, which won’t be of help to him.

Thanks for the effort though!👍

Opps . Not to knowledgeable about these but thanks for the pat on the back for effort .I try and learn

Thank you both, the 1/2 ton bushings are already finish sized when installed but the 3/4 through 2-1/2 ton bushings all need to be reamed to a specific fit. Mine is a 2 ton with the standard axle. With 40"+ tire diameter it doesn't take much pin/bushing wear to see and feel the slop. I was lucky to find a NOS set of MOOG pins and bushings, I don't want to mess them up.

buckshot,

I found this searching through available manuals at oldcarmanualproject.com.

Manual is for 1955 2nd series, so should apply to your '57 as later "Truck Supplements" showed no changes to this information through '59.

This info notes the "reamer" size to be 1.110", which would give you a clearance of 0.001" for king pin size of 1.109". Should be just right IMHO.


King Pin Reamer Info

Let us know how it turns out.

Well, that is kinda' what I was thinking also. It worries me that all of the specs are conflicting, other research tells me that it should be light hand press fit but that depends on more human error. I'll see what the machine shop owner has to say when I drop off the parts. Thank you very much for the added info, the 1957 Shop manual has that same paragraph and reamer P/N.

Forget the reamer. Have an automotive machine shop with a Sunnen honing machine line-hone the bushings for a smooth slip fit between the new bushings and the king pin after they're pressed into the spindles. I've done dozens of them that way when i was running the connecting rod reconditioning department for a big machine shop.
Jerry

Thanks Jerry, I left the knuckles, new pins and bushings at the machine shop, they have always done a great job on anything I have taken to them. I should have them back this week and start re-assembly.

I did the same thing with our 6400 king pins. I pressed the new bushings in and had a local machine shop hone them. They fit perfect. Not cheap, but I didn't have access to a reamer, so what are you going to do. I wanted them right. I found two partial sets on ebay to make one complete set with some extra parts.

Steve

I picked up my steering knuckles from the machine shop, installed the passenger side today, along with all new pins, bushings, shims, lower thrust washers, it's like new, zero slop and pivots easily. Tomorrow I hope to drain the steering gear, adjust the worm and sector, refill with 00 grease, put the drivers side all back together.

Buckshot,

Ya got any nice pictures of those fine looking parts to share?

Thank you sir!

OK, these are pics of cleaned , painted, partly assembled spindles. Waiting on new wheel seals in the mail, then I'll post pics of the wheels installed.

Thanks Buckshot. Everything looks fresh and ready for the next step.

Going to be some nice easy "wobble" free (at least for these parts) steering in the future.

Thanks for sharing.

When I get it back together there should be no play in the front end. I drained and re-filled the steering gear, adjusted the worm and sector bearing play, replace the drag link/ball ends, replaced king pins and bushings, new tie rod ends. Wheel bearings on this model are tapered roller bearings and in great shape so I can adjust them to spec.

The picture loaded with hay is from 2018. The other 3 are after I finished the steering rebuild.

Those wheels are out there for those with 20” wheels, just do some digging!

Ed

I bled the brakes today and took the truck out to the 2 lane blacktop, steering is very nice now. I might give it a touch more toe-in 'cuz the camber looks pretty heavy. The specs call for 1/8" to 1/4" toe-in, minimum toe with minimum camber and maximum toe with maximum camber. I don't have an accurate means to measure camber but it is very apparent. The caster is probably not ideal due to the 10R-22.5's in the rear and 235/80/22.5's up front but it's good enough for the girls I hang around with.