From what I can tell your left side (the 3738383 forging number in pic #3) is for a 3/4 -1 ton truck. GMC Master parts book also says that 3738383 is for a F025 (3/4 ton) or F035 (1 ton) front axle. I'm a guy who broke two left side 1/2 ton steering arms in the 23 years & 120,000+ miles I drove my '57 1/2 ton GMC. Maybe your previous owner broke his and replaced it with the wrong part. I'd also check the right side steering arm. Casting # 3711777 is the proper 1/2 ton arm. 3713017 is for 3/4 and 1 ton axles. If you have a 3/4 ton arm on the left and a 1/2 ton on the right and if the arms are different lengths, it could make for squirrely turning.
Last edited by Bill Hanlon; 11/24/2024 3:35 AM.
'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.
| 
