Those are called "road shock dampers" (if I remember correctly). I think they were standard on GMC Suburbans and available as a bolt-on for other small trucks. Somewhere I have a GMC document on them, but I've been looking for 20+ minutes and no luck so far.
No hydraulics in them, just springs and a weight.
Last edited by Bill Hanlon; 12/13/2024 4:03 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.
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