Product Description
Restore compression and durability on your 2003–2004 5.9L Cummins with INDUSTRIAL INJECTION’s STOCK piston set in .040” oversize. Built to OE geometry for clean combustion and long service life, this full set is ideal for stock and tow builds that need a fresh overbore.
Fitment
- 2003–2004 Dodge Ram 2500/3500 with 5.9L Cummins ISB (24-valve Common Rail)
What’s Included
- (6) Stock-spec pistons — .040” over (1.00 mm)
- Matched rings, wrist pins, and clips
Key Features
- OE-style bowl design and compression ratio for reliable daily/tow use
- .040” overbore sizing to recover proper clearances after machining
- Delivered as a complete, ready-to-install piston set
Recommended Parts (CPP internal links only)
- ARP 247-4202 Head Stud Kit (1998.5–2024 Cummins 5.9/6.7)
- MAHLE HS54556 Cylinder Head Gasket Set — 2003–2007 5.9L
- 03–07 Cummins Engine Parts Category (bearings, seals, pumps)
- Pistons & Rings Category (ring sets, single-cyl kits, competition options)
Cross-Reference / Alternatives
Helpful Notes
- Machine work required: Bore/hone to .040” over and set ring end gaps to spec.
- Confirm bowl design/CR against your ECU calibration and injector spray to maintain drivability and emissions function.
FAQ
Do these pistons include rings and pins?Yes—this set ships with matched rings, wrist pins, and clips for a complete installation.
Is .040" over safe for a street/tow build?Yes. .040" is a common service overbore. Always verify cylinder wall thickness and finish with your machinist.
Should I add head studs on a stock-ish rebuild?Head studs improve clamping and gasket life, especially if towing or running added boost. They’re a smart upgrade while the head is off.
What if I only need one cylinder?Use a per-cylinder OE kit like Cummins 4089977 in .040" (linked above) to service a single hole and match the others.
