1999/02/15 Caterpillar

New Auxiliary Drive Coupling Group Improves Service Life {3252}

Usage:

994 (9YF) Wheel Loaders

Description of Change: A new rear auxiliary drive coupling is used on 994 Wheel Loaders. The new larger drive coupling group improves the balance of the drive train. Because the new coupling group is larger, new smaller caps are used on the steering pumps to prevent interference.

Adaptable To: The new 148-2711 Rear Auxiliary Drive Coupling Group is a direct replacement for the former 7I-4899 Rear Auxiliary Drive Coupling Group (not serviced). When the new 148-2711 Rear Auxiliary Drive Coupling Group is used, replace the existing caps of the 9T-8993 Pumps new smaller 128-8981 Caps. (See Illustration for location of pumps). The new 148-2711 Rear Auxiliary Drive Coupling Group together with the new 128-8981 Cap are effective with 994 (9YF219) Wheel Loader and are adaptable to all earlier machines.

8X-0080 Steering and Brake Cooler Pump & Mounting Group (not serviced) showing location of new 9T-8993 Pumps and 128-8981 Caps.

Caterpillar Information System:

1999/02/15 Correction To Disassembly And Assembly Manual, RENR2116 {0374,1387}

1999/02/15 Correction To Operation & Maintenance Manual, SEBU6492-02 {0374,0375,7490}

1999/02/15 New Thrust Washer Improves Service Life Of Differential Group {3258}

1999/02/15 Correction To Operation & Maintenance Manual SEBU6955 {0374,0375,7560}

1999/02/15 Bolts, Washer, And Spacers Grouped Into Fastener Groups In Engine Cylinder Head Groups {1100}

1999/02/15 Electrical System Schematic, SENR1864, Available {1400}

1999/02/08 New VIMS Application Guide Available {7601,0374}

1999/02/08 Correct Seal Usage Improves Service Life {7555}

1999/02/08 New Engine Pressure Sensors Available {1916,1917,1922,1923,1924}

1999/02/08 Valve Bodies Now Stress Relieved To Improve Service Life {3167}

1999/02/08 Special Instruction, "Installation Instructions For Improved Ride Control System", Now Available {0374,1408,4812,5051,5057,5077,5479,7332}

1999/02/08 Correction To Testing And Adjusting Manual, RENR2146-01 {0374,1435,5700}

1999/02/15 100 cm Of 5P-1471 Hose Required For each 994 Wheel Loader Dust Ejector {1068}

1999/02/15 New Weld Procedures On 994 Wheel Loader Buckets Increase Service Life {6101}

1999/02/15 Rework Procedure Available To Upgrade Differential Case Assembly {3258}

1999/02/15 Air Conditioning And Heater System Updates Improve Operation And Reliability {7304,7309,7337,7343}

1999/02/15 New Brake Disc Wear Specifications {4250}

1999/02/22 Improved Radiator Cores Now Available {1353}

1999/02/22 Improved Hydraulic Accumulator Mounting Clips Available {5077}

1999/02/22 Engine Control Axle Protection Override {1902}

1999/02/22 Correction To Service Brake Disc Information {4250,4255,7473}

1999/02/22 Shielded Metal Arc Welding And Flux Cored Arc Welding Information {0679}

1999/03/01 Washers Added To Avoid Bolt Interference On The D6G And D6G SR Hydraulic Pump{3108}

1999/03/01 Larger Capacity Power Train And Transmission Oil Filter{3005}