In 1988 The Caterpillar 931C crawler loader was introduced to replace the Caterpillar 931B.
The 931C has a four-cylinder 67 flywheel horsepower (FWHP) 3204 direct injection engine. It comes standard with modified undercarriage and steering clutch and brake linkage.
It was available in two tack gauges – the standard model has a gauge of 56 inches (142 cm) and the Low Ground Pressure (LGP) configuration has a 65-inch (165-cm) gauge.
The 2BJ and 6RF units have a three speeds forward, three reverse powershift transmission. The 7HF and 8AF units have a three speeds forward, one reverse powershift transmission. The 5LG has a five speeds forward, four reverse direct drive transmission.
In 1990 three 931C Series II crawler loaders were introduced (2AK, 6AJ, 9AG). They all come standard with a ground engaging tool (GET) option, a new operator station, and increased breakout force.
The 2AK and 6AJ both have a three speeds forward, three reverse transmission. The 9AG has three speeds forward, one reverse. Production of the 931C Series II ended in 1993.