Cat® en์gines deliver fuel and oil economy. For example, the 3500 Family has low oil consumption at 0.5 g/bkW-hr (.0016lb/bhp-hr). Proven low-friction three-ring pistons, a four-stroke cycle combustion system, turbocharging and aftercooling and direct injection fuel system combine to deliver fuel efficiency with top performance. The new generation 3500B electronic engines keep an even tighter rein on fuel.