D6K Track-Type Tractor Caterpillar

Note: S·O·S oil analysis must be performed at every 500 service hours or 3 months to extend the hydraulic oil change interval. The normal hydraulic oil change interval is every 2000 service hours or 1 year. By performing S·O·S oil analysis, the hydraulic oil change interval may be extended to 4000 service hours or 2 years. If S·O·S oil analysis is not available, the hydraulic oil change interval must remain at every 2000 service hours or 1 year.

Operate the machine for a few minutes to warm the hydraulic system oil.

Park the machine on level ground. Lower all attachment to the ground. Move the parking brake switch to the ENGAGED position. Stop the engine.

Note: The Hystat transmission and the hydraulic system use a common tank.

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1. Open the rear access door on the right side of the machine.
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2. Remove hydraulic tank filler cap.
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3. Remove the rear cover plate.
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4. Connect 159-3727 Drain Tube that is stored inside the left access door to the drain valve to drain the hydraulic oil into a suitable container.
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5. Install the rear cover plate .

6. Change the hydraulic system filters. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Filter - Replace" and “Hydraulic System Oil Filter (Winch) - Replace” (If Equipped).

7. Fill the hydraulic system oil tank. Refer to Operation and Maintenance Manual, "Lubricant Viscosities" and Operation and Maintenance Manual, "Capacities (Refill)".
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8. Install the hydraulic cap.

9. Start the engine and run the engine for a few minutes.
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10. Maintain the hydraulic oil level above the "ADD" mark on the sight gauge . Add oil, if necessary.

    Note: The oil must be free of bubbles. If bubbles are present in the oil, air is entering the hydraulic system. Inspect the suction hoses and the hose clamps.

11. Stop the engine.

12. If necessary, tighten any loose clamps and any loose connections. Replace any damaged hoses.