The Earthmoving Legacy Center in Elkader, Iowa showcases a beautifully restored Caterpillar 660 motor scraper. This single-engine behemoth, a predecessor to the iconic twin-engine Caterpillar 666, offers a glimpse into the history of heavy equipment. It’s remarkable that these machines, with production ceasing nearly 45 years ago, continue to operate globally, testament to their robust construction.
This particular Caterpillar 660 appears to feature a 650 bowl coupled with the 660 tractor unit. Powered by a single Cat D346 V8 diesel engine, this configuration generated 450 horsepower. Its bowl boasted a substantial capacity of 40 cubic yards struck and 54 cubic yards heaped. Designed for high-speed operation across long distances and relatively flat terrain, the 660 was often paired with tandem DD9G pushers for optimal efficiency.
According to available information, only 109 units of this model were manufactured before Caterpillar introduced an upgraded version. In 1969, the company launched the 660B, equipped with a more powerful Cat D346TA engine delivering 550 flywheel horsepower. This enhanced model also featured Caterpillar’s newly developed 8-speed semi-automatic powershift transmission, a significant advancement in earthmoving technology.
The restoration of this Caterpillar 660 is truly impressive. The machine’s pristine condition and the signature black smoke billowing from its exhaust stack are a sight to behold for classic heavy equipment enthusiasts. While its emissions might not meet modern environmental standards, the 660 represents a significant era in earthmoving history and continues to captivate those who appreciate the power and engineering of these massive machines.
