In 1952 GM made a simple change to the accelerator linkage that made a major reduction in engine noise in the cab. This was definitely an improvement when older engines had developed excessive valve train noise.
Prior to this year the horizontal accelerator rod from the carburetor attached directly to the metal backing of the foot gas pedal. Engine noise was easily transferred to the pedal and into the cab.
A minor modification in 1952 eliminated much of this noise. Engineers placed a small ball on the end of the accelerator rod and a rubber receiver cup on the new foot pedal. Now noise stopped at the rubber cup and is dropped over 75% in the cab.
This GM improvement cost little when added to new trucks but made a big difference to driver comfort, particularly in the vehicle’s later years.
This later design easily replaces the original 1947-1951 style system. The later, 1952-57 accelerator pedal should be available from all older GM truck parts stores and the used 1952-1955 linkage rods can be found with limited research.