TRANSMISSION 10R8426 - Caterpillar

Hydraulic System Oil
Change the Oil
At operating temperature, the hydraulic tank is hot and under pressure.Hot oil can cause burns.Remove the plug only when the engine is stopped, and the plug is cool enough to touch with your bare hand.
Do not try to operate any control lever before air in the hydraulic system has been released completely. Failure to do so could cause damage to the actuator.
1. Steam clean the pump, hydraulic lines and hydraulic tank. 2. Position the machine as shown above. 3. Remove the hydraulic tank pressure cap.4. Remove the fill plug. 5. Oil drain valve is located under the hydraulic tank. 6. Remove the oil drain valve plug.7. Install a pipe (with 1- 11 -1/2 NPSM threads) and hose to open drain valve. Drain into a container.8. Remove the pipe to close the drain valve.9. Inspect O-ring and replace if worn or damaged.10. Clean and install the plug. 11. Remove the plug from tube and allow oil to drain into a container.12. Clean plug, add pipe sealant to plug and tighten the plug into the drain port.13. Change or clean the hydraulic system filter elements. See "Hydraulic System" in the "Every 500 Service Hours or 3 Months" section. 14. Fill the hydraulic system oil tank. See "Refill Capacities."15. Install the fill plug. 16. Inspect, clean and replace the pressure cap, if damaged.17. Install the pressure cap. 18. Open the side cover at the right of the machine. 19. Remove the pipes and fittings indicated by the arrows, and add oil up to the opening of the filler port.20. Reinstall the pipes and fittings correctly.21. Close the side cover.22. Start and operate the engine at idling speed for five minutes. 23. Operate the control levers to allow the hydraulic oil to circulate through all hydraulic circuits. Then lower the bucket to the ground with the stick vertical to the ground, as shown above, and stop the engine. 24. Maintain the oil level between the marks on the dipstick in the appropriate temperature range.