Product Description
Interstate-McBee M-4089181 Piston Ring Set – .020" Oversize (0.50 mm) – 2003–2007 5.9L Cummins ISB
.020" (0.50 mm) oversize piston ring set for the 2003–2007 5.9L Cummins ISB (24-valve common-rail). Quality aftermarket replacement engineered to OE form, fit, and function for dependable sealing and oil control. Sold for one cylinder (one piston).
- Correct oversize: .020" (0.50 mm) for use with matching .020" oversize pistons and properly bored/honed cylinders.
- OE-equivalent performance: Designed to restore compression, control blow-by, and manage oil consumption.
- Durable construction: Three-ring design (top compression, second compression, oil control assembly).
- Interstate-McBee value: Premium materials and consistent ring land fitment at an aftermarket price.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-4089181 |
| Size / Oversize | .020" (0.50 mm) oversize |
| Engine | 5.9L Cummins ISB (24-valve common-rail) |
| Years | 2003–2007 |
| Sold As | Set for one piston (one cylinder) |
| Qty Required (complete engine) | 6 ring sets |
| Position | Piston ring set (top/second/oil) |
What’s Included
- (1) Top compression ring
- (1) Second compression ring
- (1) Oil control ring assembly (rails + expander)
Vehicle / Engine Fitment
Always verify by engine serial number (ESN) and piston size.
- Dodge Ram 2500/3500 with 5.9L Cummins ISB (24-valve common-rail)
- Model Years: 2003, 2004, 2004.5, 2005, 2006, 2007
- Other B-Series/ISB applications where Cummins specifies 4089181 and .020" oversize rings (confirm by ESN).
Install Notes
- .020" oversize rings require matching .020" oversize pistons and cylinders bored/honed to spec.
- Check and set ring end gaps per the service manual; verify orientation/markings before installation.
- Use proper cylinder finish and cleanliness for ring seating; lubricate as directed by the manual.
- Stagger ring end gaps according to recommended positioning; do not align gaps.
FAQ
How many sets do I need?
One set services one piston. Order six (6) sets for a complete 5.9L engine.
Will these fit stock-size pistons?
No. These are .020" oversize. Use only with .020" over pistons and properly machined cylinders.
Does this fit the 6.7L Cummins?
No. This listing is for 5.9L ISB (2003–2007) only.
