The Cummins/Onan 4B3.9 engine line groups 3 variant designations. Parts and fitment are pooled here so a cross-reference found on one variant surfaces for the whole family.
| Part # | Description | Category |
|---|---|---|
| 928-0502B | other_service | |
| 928-0506 | other_service | |
| 960-0135 | other_service | |
| 960-0504A | other_service | |
| 960-0505 | other_service | |
| 960-12 | other_service |
Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.