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The front axle presented a challenge when I discovered some time ago that the left end king pin hole was worn oversize. I took the axle down to a friend's machine shop to use his Bridgeport mill. Typically, the set up took much longer than it did to bore out the hole so I could install a bushing. Back at my shop, I made a new bushing out of 4140 steel. The bushing was only .020" thick, so using a press to install it was not an option. I put the bushing in the freezer for a couple days and the axle in a warm room near a heater. When the time came, the bushing installed with a light tap from a rubber hammer. After the temperature equalized, the bushing was held fast in place. I then used an adjustable reamer to increase the inside diameter of the bushing to .922" (the new king pins, from ClassicParts.com, are .921"). Finally, I cleaned up the cross pin hole with a 1/2" tapered reamer.

Next up was new bushings in the spindles. Using the lathe, I made a tool out of some bar stock that would fit just inside the spindle holes to press out the old bushings, and press in the new ones. The unusual shape of the spindle castings made setting them up in the press a real juggling act. I had to cut notches in a couple pieces of 3" channel to fit around the spindle itself and give it something flat to rest on. Once the new bushings were in, I used the same adjustable reamer to get the new bushings to the .923" called for in the shop manual. The reamer that I used is not long enough to ream both bushings at the same time (as the proper GM tool would have done) so I had to take great care to ensure that the two holes were in line. It was a long, slow process so I've only got one spindle done at this time.

My son is off work this week so he came home and helped me install the repaired front axle back under the front of the truck.