The Cummins/Onan 6BT5.9-G6 is a 5.9 L 6-cylinder turbocharged engine rated at 1800 rpm, producing up to 126.8 kW. It powers generator sets from Cummins/Onan, including the C110D6, C120D5 and DGDB. It holds 16.4 L (4.3 gal) of oil and 24.6 L (6.5 gal) of coolant.
Also known as: Cummins 6BT5.9-G6
Part of the Cummins/Onan 6BT5.9 engine family — 6 variants share parts & fitment.
| Oil capacity | 16.4 L |
|---|---|
| Coolant capacity | 24.6 L |
| Displacement | 5.9 L |
| Cylinders | 6 |
| Aspiration | Turbocharged |
| Rated speed | 1800 rpm |
| Gross power | 126 kW |
| Part # | Description | Category |
|---|---|---|
| 982-0200 | Air Filter | air_filter |
| 3824469 | fuel pump gear puller | fuel_pump |
| DM-3801372 | Gasket Set - 6BT 5.9 | gasket |
| FP-6B59PREM | 6B/6BT5.9 In-Frame Kit w/upper gasket set & oil pan gasket | gasket |
| FP-6B59PREML | 6B/6BT5.9 In-Frame Kit w/upper gasket set & oil pan gasket (late) | gasket |
| FP-IFK6B59PREM | 6B/6BT5.9 In-Frame Kit w/upper gasket set & oil pan gasket | gasket |
| FP-IFK6B59PREML | 6B/6BT5.9 In-Frame Kit w/upper gasket set & oil pan gasket (late) | gasket |
| 3822509 | injector puller | injector |
| 3823276 | injector bore brush | injector |
| DM-3029551 | Fuel Injector - 6BT 5.9 | injector |
| LF3349 | Lube, Full-Flow Spin-On | lube_filter |
| 3377259 | bosch timing tool (ve) | other_service |
| 960-0627C | other_service | |
| 965-0520 | Cooling Fan | other_service |
| DM-3802010 | Main Bearing Set Standard - 4BT 3.9, 6BT 5.9, 6CT 8.3 | other_service |
| FP-3356970 | 6B/6BT5.9 In-Frame Kit (contains FP-3802160 Piston Kit) | other_service |
| FP-3356971 | 6B/6BT5.9 In-Frame Kit (contains FP-3802248 Piston Kit) | other_service |
| GM12641 | Safety/locking agent | other_service |
| GM12657 | Dipstick | other_service |
| GM12676 | Cylinder liner | other_service |
| GM12678 | Screw plug | other_service |
| GM12697 | Torx-head bolt | other_service |
| GM12921 | Hexagon bolt | other_service |
| GM12924 | Rear end cover | other_service |
| GM12936 | Wrapped bearing bush | other_service |
| GM12937 | Wrapped bearing bush | other_service |
| GM12954 | Dipstick | other_service |
| GM12970 | Compression spring | other_service |
| GM13175 | Pipe clamp | other_service |
| S103 | selector switch on the control PCB | other_service |
| TB1-6 | terminals between TB1-5 and TB1-7 in the control box | other_service |
| TB1-7 | terminals between TB1-6 and TB1-8 in the control box | other_service |
| DM-3805401 | Oil Pump - 6BT 5.9 | pump |
| DM-3805403 | Water Pump - 4BT 3.9, 6BT 5.9 | pump |
| GM12667 | Sealing ring | seal |
| DM-3015282 | Thermostat 180F - 4BT 3.9, 6BT 5.9 | thermostat |
Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.
The Cummins/Onan 6BT5.9-G6 engine has an oil capacity of 16.4 liters.
The Cummins/Onan 6BT5.9-G6 has a displacement of 5.9 liters with 6 cylinders.
The Cummins/Onan 6BT5.9-G6 powers 3 generator set(s), including Cummins/Onan C110D6, Cummins/Onan C120D5, Cummins/Onan DGDB.