TM 11-6615-241-35-1-2 Planned Maintenance and Lubrication Hydraulic Fluid Level Check Check the hydraulic sump tank oil level with: 1. Truck on a level surface. 2. Upright in a vertical position. 3. Fork carriage fully down. 4. Oil at operating temperature. Pull the dipstick out, wipe it with a clean wiper, and push it back into the dipstick tube.  Pull the dipstick out again and check the oil level. The hydraulic sump tank oil level should be up to the "F" (full) mark on the dipstick. Approximately 1.0 gal (3.8 L) of hydraulic oil is required to fill the hydraulic tank from the "L" (low) mark to the "F" (full) mark.  Do not overfill. Hydraulic Sump Tank Fluid & Filter Change CAUTION Use recommended fluid only.  Failure to     use     recommended     fluid     could result in damage to equipment. It is recommended to: • Drain and replace the hydraulic fluid every 2000 operating hours. • Replace the hydraulic oil filter at every oil change. • Replace the hydraulic sump tank breather/fill cap every 1000 operating hours. E-100