Product Description
The CUMMINS 4089977 OEM PISTON KIT (.040 OVER) is designed for 2003–early 2004 5.9L ISB Cummins 305 HP common-rail diesel engines. This genuine Cummins piston kit is manufactured to OEM specifications and is intended for engine rebuilds requiring a .040-inch oversize piston to restore proper cylinder clearance, compression, and engine performance.
Use this piston kit when rebuilding an engine with cylinders that have been bored .040-inch oversize due to wear, scoring, or damage. Always verify engine CPL, piston size, and application before ordering.
FEATURES
- Genuine Cummins OEM piston kit
- .040-inch oversize piston for machined cylinder bores
- Designed for 2003–early 2004 ISB 5.9L 305 HP common-rail engines
- Helps restore proper compression and engine efficiency
- Ideal for engine overhaul, repair, and rebuild applications
- Manufactured to Cummins OEM specifications
FITMENT
- 2003–Early 2004 Dodge Ram 2500 5.9L Cummins 305 HP Common Rail
- 2003–Early 2004 Dodge Ram 3500 5.9L Cummins 305 HP Common Rail
- Select Cummins ISB 5.9L industrial applications using this piston specification
WHAT'S INCLUDED
- 1 Cummins 4089977 OEM Piston Kit (.040 Over)
- Piston rings and wrist pin as supplied by Cummins
- Associated retainers or hardware as supplied by Cummins
CROSS-REFERENCE AND RELATED PRODUCTS
- Cummins 4089977
- Cummins Standard Bore Piston Kits
- Cummins Connecting Rod Components
- Cummins Rod Bearing Sets
- Cummins Complete Engine Overhaul Kits
SPECIFICATIONS
- Manufacturer: Cummins
- Part Number: 4089977
- Part Type: Piston Kit
- Piston Size: .040 Inch Oversize
- Engine Compatibility: ISB 5.9L Cummins
- Engine Rating: 305 HP Common Rail
- Fitment Years: 2003–Early 2004
- Vehicle Application: Dodge Ram 2500 / 3500
- Condition: New OEM Cummins
FAQ
Will this piston kit fit my truck?
This piston kit is intended for 2003–early 2004 5.9L ISB Cummins 305 HP applications requiring a .040-inch oversize piston. Verify engine CPL, piston size, and machining specifications before ordering.
What does .040 over mean?
A .040 over piston is designed for an engine block that has been machined .040 inch larger than the factory cylinder bore size during a rebuild.
What is included in the kit?
The kit includes the piston and related components supplied by Cummins for the application, typically including rings and wrist pin.
Can this piston be used in a standard bore engine?
No. This piston is intended only for cylinders that have been bored .040 inch oversize. Cylinder measurements should always be verified before installation.
Is this a genuine Cummins piston kit?
Yes. Cummins 4089977 is a genuine OEM Cummins piston kit manufactured to factory specifications.
Do I need any related parts?
During an engine rebuild, inspect cylinder liners or bores, connecting rods, rod bearings, main bearings, gaskets, seals, and related engine components for wear and replace them as necessary.
