Gas Tanks

So unusual to place a gas tank under the seat with no fill pipe outside the cab! To engineer this big change for 1937 was expensive and very different from earlier years when it was under the bed. Why was this done? What advantages could this have been over an outside fill spout? Was gasoline theft during the depression years a big problem?

To add gasoline on a 1937, the right lower cushion half was raised up toward the back which exposed the threaded ‘bung’ on the surface of the tank. It meant a person stood outside by the right side of the cab, raised the cushion half and added fuel. This is how it was done! If it was raining or snowing, the driver or the attendant stood there fueling. Maybe you kept an umbrella stored in this small cab for emergencies. Maybe gas station employees knew that when a 1937 Chevrolet or GMC truck drove in to get gas in the rain, a raincoat was needed. If some gasoline was spilled while filling, the vapor was smelled throughout the cab. If you were a cigarette smoker, well—–!!!

We were fortunate to recently obtain a set of 1937 original seat cushions. Even the upholstery on the two lower halves was still intact. The non-spout gas tank from the same truck came in the set.

Before they were requested by a serious collector, pictures had to be taken. Finding a pure set again in one place would probably be impossible.

An interesting feature is the plywood bottom on the right side removable cushion. The rectangular hole in the plywood prevented the springs from ever sagging and touching the electric gas sending unit. This must have been placed there to also protect the gas tank and bung from contact with a passenger’s weight on the seat. Engineers knew that a spark from an electric short near gas vapor would be a disaster!

We think these photos will be very interesting to the 1937 GM truck enthusiast. This way of tank filling continued into early 1938. Probably during the depression years, the manufacturer used their extra bodies and tanks that were left over from 1937 until supplies were depleted. Of course, this changeover would vary depending on the assembly plant.

The in- cab gas tank is also unique. It lies neatly inside the seat riser. The twist cap (bung) hole for adding fuel is at least 10′ away from the sending unit (protection from a gasoline pump add nozzle). For some reason the tank is built with two drain holes. One is always plugged and therefore the tank can be used in two type cabs. Maybe the gasoline outlet is different for right or left hand drive trucks!

Both Cushions have original upholstery	Easily removable wood bottom half cushion. Note: the 2 small blocks to keep cushion secure on the seat riser.
Open spring half cushion for driver	Both cushions raised above gas tank.
Plywood notch fits above gasoline sending unit.	Sending unit in place.
Gasoline add bung and adjacent air vent.	Open bung during refueling.
Top of tank. Note: Sending unit, bung, and air vent.	Bottom of tank. Note: 2 Gas outlets.

Amendment to 1937 to Early 38 Chevrolet / GMC Gas Tank and Seat Cushions:

Several years after the above article was posted, a pair of original bottom cushions appeared at our shop. The owner stated they were from a 1937 pickup that had been in the family since it was a year old.

As the underside is covered with a sheet of rusted thin metal, it would appear it is original GM. We now wonder if the wood plywood bottom in the first article is factory installed or the result of a very skilled carpenter attempting to add additional years to a deteriorated set of original cushions. You be the judge!