771D Quarry Truck

Power Train – TransmissionThe Cat 6-speed, power shift transmission gets the job done smoothly and quickly.■ Economy shift mode. gears match Cat engine design for1324Transmission. The Cat 6-speed,power shift transmission, matchedwith the direct-injection 3408E dieselengine provides constant power over1 Lock-up Torque Converter. Combinesthe maximum rimpull and cushionedshifting of torque converter drivewith the efficiency and performanceAxles. Full floating axles are shotpeenedto relieve internal stresses andincrease durability. Rolled splines alsoprovide increased service life.a wide range of operating speeds. of direct drive.Wheels and Rims. Cast rear wheels■ Engages at approximately 6.9 km/h,Transmission Features.and Cat center-mount rims aredelivering more power to the wheels.■ 6 speeds forward, one reverse.mounted using studs and nuts to■■Lock-up clutch quickly releases andTorque converter driven reverse.minimize maintenance and maximizere-engages during shifts, maintaining■ 1st gear has both torque converterdurability.power wind-up, improvingdrive and direct drive.transmission life and increasingTransmission Chassis Controller■ 2nd through 6th gears are directoperator comfort.(TCC). TCC uses electronicallydrive.transferred engine rpm data to execute■ Single-lever shift control provides 2 Planetary Power Shift Transmission.shifts at preset points for optimumautomatic shifting in all gears up to Utilizes a modulating pressure valve toperformance and efficiency.the one selected by the control lever. regulate clutch pressure rise and fall toThis integration allows:■ Each shift is individually modulated ease clutch engagement. This reduces■ Programmable top gear limit.for maximum smoothness.shock loads on power train components.■■Control throttle shifting.Separate hydraulic circuit withFeatures include:■■Directional shift management.cooler.Large diameter clutches and robust■■Neutral coast inhibitor.Electronic control has built-inplanetary gears and bearings.■■Economy shift mode.diagnostics and fault code memory, Patented rotating clutch pressure sealsevent memory and programmablefeatures.minimize drag losses and improvereliability.Integration. The Caterpillar powertrain integration provides increased■ Control throttle shifting.■ 35 percent gear splits between all component life and operator comfort.optimum use of engine power withminimized shifting and torqueconverter use.3 Final Drive. Final drive and differentialtorque multiplication of 13.15:1 furtherreduces stress on the drive train.4 Sump. Transmission and torqueconverter share a common sump.The combined sump offers an easilyaccessible fill tube and sight gauges.6