07-19 Dodge Ram 4956007 Piston +0.5mm for Cummins QSB6.7 ISB 4B Replace No. 5255257

For a 2007.5–2019 Dodge Ram 6.7L Cummins (ISB 6.7L), the 4956007 (+0.5mm) piston is not a direct OEM replacement for factory pistons, but it may work in a rebuilt engine under certain conditions. Here’s what you need to know:

1. Does 4956007 Fit a 2007.5–2019 Dodge Ram 6.7L Cummins?

• Original Application:

  • This piston is primarily for industrial/marine Cummins QSB6.7 & ISB 4B engines, not specifically for Dodge Ram trucks.

  • Replaces Cummins #5255257, which was used in off-road/marine applications.

• Ram 6.7L Compatibility:

  • The Dodge Ram 6.7L (2007.5–2018/19) uses different OEM pistons (e.g., Cummins #4026253, #4026254 for standard sizes).

  • 4956007 is an oversize piston (+0.5mm), meaning it requires the block to be bored out.

  • Possible fit? Some aftermarket suppliers list it for Ram 6.7L rebuilds, but it’s not a factory-specified part for Dodge applications.

Compatibility with Dodge Ram:

1. 2003–2007 Dodge Ram 5.9L (ISB)

   • The ISB 4B designation typically refers to the 5.9L Cummins (2003–2007) in Dodge Rams.

   • If your engine is a 5.9L Cummins (ISB), this piston may fit, but you must confirm:

     • Bore size: The engine must have been machined to accept a +0.5mm oversize piston.

     • Piston configuration: Verify that the piston design matches (e.g., bowl shape, wrist pin size).

2. 2007.5–2018 Dodge Ram 6.7L (ISB/QSB6.7)

   • The QSB6.7 is the industrial/marine version, but the 6.7L Ram Cummins (ISB 6.7) shares some parts.

   • Check part cross-references—some aftermarket suppliers list this piston for 6.7L Rams, but OEM applications may differ.

• Original Part #5255257 was used in industrial/marine Cummins engines, not necessarily in Dodge Rams.

• Always verify engine serial number & bore condition before using an oversize piston.

• Best to cross-check with Cummins Quickserve or a dealer to confirm fitment for your specific Ram.

2. Key Considerations Before Using This Piston

• Bore Size Requirement:

  • Your engine block must be machined to 107.5mm (stock is 107mm) to use this piston.

  • If you’re doing a rebuild, confirm with your machine shop.

• Piston Design Differences:

  • Industrial pistons (like 4956007) may have different bowl shapes, ring lands, or wrist pin sizesthan Dodge Ram pistons.

  • Verify compression ratio and turbo compatibility (industrial engines sometimes run different specs).

• Best for:

  • High-performance or custom builds where the engine is being modified.

  • Not ideal for a stock rebuild—use OEM or aftermarket pistons specifically for Ram 6.7L.

3. Recommended Alternatives for Dodge Ram 6.7L

If you need a +0.5mm piston for a Ram 6.7L Cummins, these are better choices:

• OEM Pistons:

  • 4026256 (Standard)

  • 4026257 (+0.5mm oversize)

• Aftermarket Options:

  • Mahle, NPR, or DSS Pistons (designed specifically for Ram 6.7L).

4. How to Confirm Fitment

1. Check Engine Serial Number in Cummins Quickserve.

2. Consult a Machine Shop—they can compare dimensions.

3. Verify with a Cummins/Dodge dealer before purchasing.

Final Verdict:

• 4956007 can work in a Ram 6.7L if the block is bored correctly, but it’s not the ideal factory-specified piston.

• For a reliable rebuild, use a Dodge-specific piston (like #4026257 or aftermarket equivalents).

Would you like help finding a verified +0.5mm piston for your Ram? Let me know!