Oil capacity: 18.9 L (20.0 US qt) (C8.3). The Cummins/Onan C8.3 engine line groups 2 variant designations. Parts and fitment are pooled here so a cross-reference found on one variant surfaces for the whole family.
| Variant | Displacement | Cylinders | Rated rpm | Oil capacity | Coolant |
|---|---|---|---|---|---|
| C8.3 | 8.3 L | 6 | 1,470 | 18.9 L (20.0 qt) | 22.3 L |
Each figure is from that variant’s own documents (see its engine page for sources). Oil capacity can differ between applications of the same engine; check the manual for your generator set.