08/28/2026
“The smoothest running engine I think Caterpillar ever built.”
That’s how former Caterpillar engineer Jim Coles remembers the D318.
Found in machines including the Cat D6, No. 18 Motor Grader, and 977 Track Loader, the D318 was remarkably smooth.
Jim’s test? You could put a teacup on top of it and it wouldn’t bounce off.