| Fuel Tank Water and Sediment | Drain | 50 hr | | Every 50 Service Hours or Weekly. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Cooling System Coolant Sample (Level 1) | Other | 250 hr | | Every 250 Service Hours - Obtain. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Battery Electrolyte Level | Check | 500 hr | 12 mo | Every 500 Service Hours or 1 Year. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Cooling System Coolant Sample (Level 2) | Other | 500 hr | 12 mo | First service — Initial 500 Hours (for New Systems, Refilled Systems, and Converted Systems) - Obtain. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Engine Valve Lash | Adjust | 1000 hr | | Every 1000 Service Hours - Inspect/Adjust. Initial adjustment recommended at the first scheduled oil change. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Cooling System Water Temperature Regulator | Replace | 3000 hr | 36 mo | Every 3000 Service Hours or 2 Years. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Fuel Injection Nozzles | Test | 3000 hr | | Every 3000 Service Hours - Test/Exchange. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Cooling System Coolant Extender (ELC) | Other | 6000 hr | 36 mo | Every 6000 Service Hours or 3 Years - Add. Schedule for X3B1-Up, XYC1-Up, XYD1-Up, N4R1-Up, N3X1-Up, N4X1-Up |
| Alternator | Inspect | 2000 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Alternator Belt | Inspect | 500 hr | 12 mo | Every Year - Inspect/Adjust/Replace. Schedule for D4D1-Up, GLE1-Up |
| Battery | Replace | | 36 mo | Every 3 Years. Schedule for D4D1-Up, GLE1-Up |
| Cooling System Coolant (ELC) | Change | 12000 hr | 72 mo | Every 6 Years. Schedule for D4D1-Up, GLE1-Up |
| Engine | Clean | | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Engine Air Cleaner Element (Single Element) | Replace | 500 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Engine Mounts | Inspect | 2000 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Engine Oil Sample | Other | 500 hr | 12 mo | Every Year - Obtain. Schedule for D4D1-Up, GLE1-Up |
| Engine Oil and Filter | Change | 500 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Fuel System Primary Filter (Water Separator) Element | Replace | 500 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Fuel System Secondary Filter | Replace | 500 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Generator Set Vibration | Test | 2000 hr | 12 mo | Every Year - Test/Record. Schedule for D4D1-Up, GLE1-Up |
| Hoses and Clamps | Inspect | 500 hr | 12 mo | Every Year - Inspect/Replace. Schedule for D4D1-Up, GLE1-Up |
| Insulation | Test | 100 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Rotating Rectifier | Check | 1000 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Starting Motor | Inspect | 2000 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |
| Water Pump | Inspect | 3000 hr | 12 mo | Every Year. Schedule for D4D1-Up, GLE1-Up |