Product Description
CUMMINS 4955366 OEM PISTON RING SET (STANDARD) – ISB 6.7L (2007.5–2015)
The genuine CUMMINS 4955366 OEM piston ring set is the factory-standard ring kit for 2007.5–2015 6.7L ISB Cummins engines. High-quality piston rings are essential for maintaining proper compression, sealing, oil control, and long-term durability. This set is engineered by Cummins to meet strict specifications for metallurgy, tension, and wear resistance—ensuring the correct fit and performance during engine rebuilds or top-end refreshes.
This standard bore ring set is designed for OEM cylinders that remain within standard serviceable tolerances. If you are rebuilding a high-mileage 6.7L, correcting blow-by, repairing scoring, or restoring compression, installing authentic Cummins rings guarantees a reliable, leak-free seal and optimized combustion.
Key Features
- Genuine Cummins OEM piston rings – built for exact tolerances.
- Standard bore size – used with non-machined or lightly worn cylinders.
- Engineered for optimal compression and oil control.
- High-strength metallurgy withstands heavy-duty 6.7L operating temperatures.
- Direct fit for ISB 6.7L engines from 2007.5–2015.
Fitment Details
- Engine: Cummins ISB 6.7L
- Years: 2007.5–2015
- Vehicle Applications: Ram 2500 / 3500, Cab & Chassis, ISB industrial platforms
- Bore Size: Standard (STD)
- Notes: Always verify ring size using VIN/ESN and cylinder measurements.
Cross-Reference & Companion Cummins Parts
CPP Diesel carries the full lineup of Cummins engine rebuild components that pair with CUMMINS 4955366, including:
- CUMMINS 4376347 STANDARD PISTON KIT – ISB 6.7L
- CUMMINS 5257967 MAIN BEARING SET – STANDARD
- CUMMINS 4981790 VALVE STEM SEAL – 5.9L/6.7L
- CUMMINS 4955212 EXHAUST VALVE KIT – 6.7L
- CUMMINS 5257148 INTAKE VALVE KIT – 6.7L
- VIEW MORE GENUINE CUMMINS OEM ENGINE PARTS
Cross-reference numbers: 4955367, 4955368 (oversize options; verify by VIN/ESN).
Installation Notes
- Measure cylinder bore taper and out-of-round before installing rings.
- Confirm end-gaps according to Cummins specifications.
- Honing the cylinder walls is recommended for proper ring seating.
- Install rings in correct orientation and stagger end-gaps.
- Use assembly lube and follow Cummins torque procedures during reassembly.
Specifications for cummins 4955366
| Attribute | Value |
|---|---|
| Brand | Cummins (Genuine OEM) |
| Cummins Part Number | 4955366 |
| Alternate Part Numbers | 4955367, 4955368 (oversize) |
| Function | Standard bore piston ring set |
| Engine Compatibility | Cummins ISB 6.7L (2007.5–2015) |
| Bore Size | Standard (STD) |
| UPC | 190910289612 |
| GTIN | 190910289612 |
| Shipping Weight | Approx. 0.45 lbs |
| Shipping Method | Standard ground; expedited available |
| E-Codes / Emissions | Non-emissions internal engine component |
| Prop 65 Warning | WARNING: May expose you to chemicals known to the State of California to cause cancer and reproductive harm. See www.P65Warnings.ca.gov. |
| Country of Origin | As labeled by Cummins (varies by batch) |
Frequently Asked Questions
WILL THESE RINGS FIT MY 6.7L CUMMINS?
Yes. CUMMINS 4955366 fits most standard-bore ISB 6.7L engines from 2007.5–2015. Always verify ring size using VIN/ESN.
HOW DO I KNOW IF I NEED STANDARD OR OVERSIZE RINGS?
You must measure your cylinder bores. Oversize rings (4955367/4955368) are used when cylinders are machined or out of specification.
SHOULD I HONE THE CYLINDERS WHEN INSTALLING NEW RINGS?
Yes. Honing ensures proper ring seating and long-term compression sealing.
ARE THESE GENUINE CUMMINS RINGS?
Yes — this is an authentic Cummins OEM ring set supplied by CPP Diesel.
