Mack Trucks positioned for long-term success
May 1, 2010 12:00 PM
Mack Trucks continued...
The mDRIVE has 12 forward and four reverse speeds, and is available in direct drive or overdrive. It has a torque capacity of 1920 lb-ft and a dry weight of 615 pounds. The shifting strategy for mDRIVE is optimized for North American highway conditions and is based on cruise speeds of 1350 to 1450 rpm for best performance and fuel economy.
The driver interacts with mDRIVE through a dash-mounted control pad containing manual input and hold shift buttons, with an integral display indicating the current gear. In addition, the Co-Pilot driver display in the center of the instrument panel provides the driver with transmission status, including the number of upshifts or downshifts available, the current gear and the current operating mode (such as Economy or Performance).
The transmission's Economy mode maximizes time spent in top gear, while Performance mode maximizes gradeability. An additional MackCellerator or kick-down feature drops the transmission one gear (while synchronizing engine RPM) when the accelerator pedal is sharply depressed beyond its detent to maximize acceleration in passing situations.
mDRIVE is available in two versions: Fleet and Premium. The Fleet package includes basic shifter controls, with Grade Gripper and MackCellerator as options. The Premium package consists of a shifter with more features for greater driver control, including manual shift inputs, performance and economy modes, plus Grade Gripper and MackCellerator. mDRIVE is available with two optional rear-mounted power take-offs (PTO).
The new automated transmission has an extensive list of customer-programmable parameters and functions, so performance can be dialed in for a specific customer application.
Other notable mDRIVE features include:
Cruise'n Brake, which limits engine brake operation while in cruise control until the target speed has been reached
Gear selection adjustment in auto mode, which allows the start gear and driving gear to be manually selected using the Premium shifter
Low Speed Modulation control, which enables clutch management at very low vehicle speeds when using the brake pedal to control vehicle speed, such as when backing into a loading dock or driving onto a weigh scale
Customer predefined splitter position when engaging PTO operation
Auto Neutral, which automatically shifts the transmission to neutral if the engine has been shut off while in gear or after four minutes of idling with the parking brake applied; this prevents stalling and reduces the load on the transmission.
Mack new C150/151 rear axle carriers combine proven design with improved rear axle ratios for highway and vocational applications. “The new C150/151 carriers play a key role in the Mack Pedigreed powertrain,” said David McKenna, Mack director of powertrain sales and marketing. “They're lighter, stronger, and stiffer than previous designs and represent what Mack has learned about integrated drivetrains in the last 110 years. The rear carrier is absolutely critical to a successfully-spec'd truck, including the gear-fast/run-slow highway tractor. The new and expanded ratio coverage reflects the continuing evolution of North American powertrains.”
The C150/151 retains Mack's traditional and unique top-load, dual-reduction design. The top-loaded carrier — where the driveshaft connects to the carrier above the axle — results in near-zero driveline angles, which minimizes noise, vibration and harmonics. Potential oil leak paths are significantly reduced since the carrier joint is on the horizontal plane, above the level of the oil reservoir. Dual reduction reduces gear face friction and related parasitic losses, component stress and excess heat, increasing overall component life.
Mack's power divider is standard with the new C150/151 carriers. Rear axle ratios run from 3.11:1 to 5.66:1. The new carriers are compatible with all suspensions offered by Mack.
Bendix ES (Extended Service) brakes are now standard equipment for all Mack truck models. Other brake systems, including the Bendix Air Disc, remain available options.
The Bendix ES brakes have a number of features to improve brake life and durability, while reducing operating costs:
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a fixed single anchor pin design for superior brake geometry control and longer brake life
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thicker brake linings for fewer relines
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“E-coated” brake shoes for rust prevention
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“hot staked” brake shoes for improved durability.
