In designing the panel truck, engineers realized that this vehicle must have a bumper for body protection. This bumper however, created a slight problem! It held the person loading freight further away from the vehicle cargo floor. He was required to lean further forward to reach merchandise.
To help solve this problem, GM modified the standard bumper to come closer to the middle of the body. The bumper was simply given a stamping at the manufacturer and the solution was achieved. Though it gave the worker only a few more inches, it did increase his reach.
In today's world, the indented panel truck rear bumper (1946 and older) has become difficult to find. Most panel trucks are restored with a bumper from a pickup truck. Few owners are even aware that this specially formed bumper existed.
NOTE: We assume this was for marketing to help sell more new Panel trucks!
