The new Cat 789D Mining Truck incorporates new features to boost performance and productivity and to enhance safety and serviceability. The 789D retains many of the proven technologies of the 789C, which the new model replaces. The 789D nominal payload is 181 metric tons (200 short tons), an increase of 2.5 percent from the previous model. The mechanical drive train is powered by the Cat 3516C EUI quad turbocharged diesel engine as the standard. Where applicable, the 3516C engine is compliant with U.S. EPA emissions regulations. The 3516C delivers 1566 kW (2,100 hp) gross power, about 10 percent more than the previous model, for increased speed on grade. The 3516C standard engine is capable at altitudes up to 3658 meters (12,000 feet) with no derate. The Cat 3516B engine also is available for mines requiring an engine with gross power of 1417 kW (1,900 hp) to match with existing fleets.
Caterpillar also introduces the Combination body for the 789D. Based on the dual slope design, the Combination body is a multi-purpose, high volume body designed to reduce haulage costs of well fragmented, low density material. An updated dual slope body also is available, as are X, MSD II and Dual Slope bodies—enabling mining customers to optimize their trucks for the application. The 789D has been designed to accommodate larger tires, 40.00-R57 and 42/90R57. The standard tires size is 37.00-R57. The 789D retains the proven Cat oil-cooled braking system, which combines the service, secondary, parking brake and retarding functions in the same robust system for optimum braking efficiency.
The 789D is available worldwide in an XQ configuration for reduced sounds levels in the surrounding environment. The configuration uses sound attenuating materials and designs for significantly reduced spectator sound. A number of changes extend reliability and durability. A new pump drive system provides continuous rear axle filtration. Benefits include cleaner oil, less downtime and improved component life. Extended life disc brakes are now standard equipment and may achieve up to double the wear life of the previously used brake material. The brakes are resistant to glazing and deliver consistent braking power and reduced maintenance. New air intake and filters have a new seal, which provides easier servicing and lower maintenance costs.