Originally Posted by 1Ton_tommy
The 1-tons are just over an inch not the 0.921 of the 3/4-ton.

I don't think there is any difference between the '51 Chevy 3800 and the '51 GMC 250 front axle. The '51 GMC Maintenance Manual has both the 3/4 and 1 ton axles using the same 0.921" diameter kingpin. Chevrolet Master Parts Catalog 1929-1954 shows 3/4 and 1 ton using the same part.
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'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.