Have you checked the rear cab mounts. There located near the “B” pillar. Maybe the rubber bushings are shot.
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Last edited by Phak1; 06/07/2023 5:59 PM.
Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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