2025-2026 Flat tappet conversion kit™

Hamilton Cams Complete Kit for Cummins Engines

“Innovation slightly faster than imitation.”

Forged Steel Camshafts

• Tighter Grain Structure: Our 178 steel cams are forged, not cut from bar stock—resulting in a more dense, more uniform grain structure.
• Enhanced Longevity: A natural “halo” in grain structure forms on the exterior of the cam during forging, adding a layer of strength for extended service life.

DLC-Coated Tappets

Gas Carburized & Polished: Each tappet undergoes a meticulous hardening process that creates a stable, hardened base metal for the DLC coating.

Diamond-Like Carbon (DLC) Coating: This ultra-hard surface dramatically reduces friction and wear, but proper operating conditions are critical for long service life. DLC can be damaged by incorrect oil, improper valve lash, valve float, excessive RPM, excessive spring pressure, or metal contamination. Always use a quality 15W-40 oil (or 5W-40 in sub-zero temperatures) containing adequate zinc, phosphorus, and molybdenum. Low-viscosity or low-additive oils do not provide the film strength required for flat tappet operation.

We require Valvoline Premium Blue or Schaeffer’s 15W-40 (5W-40 in sub-zero conditions). Using non-approved oil voids the warranty. Warranty claims must include the failed parts and an oil sample.

Maintain 0.010″/0.020″ valve lash, recheck lash after initial run-in and after re-torquing the cylinder head, and keep engine speed below 4,000 RPM with OEM valve springs. Excessive RPM, spring pressure, incorrect lash, or contaminated oil can break down the protective oil film, causing DLC wear or delamination. Fleetguard LF16035 Stratapore is our recommended oil filter.

Heavy-Duty Pushrods

• 3500+ lbs Buckling Force: Compared to around 1800 lbs for OEM pushrods, ours drastically reduce deflection at high cylinder pressures.
• Consistent Valve Timing: With less flex, your valvetrain stays precisely in sync—even under extreme conditions.

Upgraded Rocker Arms

• High-Quality Casting: Built to handle intense stress and heat cycles.
• Gas Carburized Ball & Foot: Reduces friction and wear for longer service intervals.
• DLC-Coated Trunnion: Minimizes galling—an all-too-common issue with OEM trunnions—and lowers overall friction in the valvetrain.

Oil Recommendations

•  Use Valvoline 15W-40 premium blue
• Schaeffer 700 Series 15w-40
• OEM Mopar filter

Proven Performance & Reliability

• Decades of Experience: Our cams have powered countless diesel engines for millions of road miles and thousands of dyno runs.
• SEMA-Certified (49-State Compliance): This kit is tested and certified for street use in 49 states, giving you peace of mind.

• Important Fitment Notice

  • If you’ve had your engine block or cylinder head surfaced, please call us for verification to ensure proper kit fitment.
  • Intake Valve Lash: 0.010″
  • Exhaust Valve Lash: 0.020″

When you choose Hamilton Cams, you’re investing in proven innovation and superior craftsmanship. Experience the confidence that comes from a kit designed to hold up under extreme conditions, and help your Cummins engine deliver reliable power for the long haul.

****we will require a core charge on rocker arms***

Approved oil — required. Use a 15W-40 (or 5W-40 in sub-zero conditions) with adequate zinc, phosphorus, and molybdenum. Thin or low-additive oils don’t provide the shear strength a flat tappet needs. Approved oils:

• Valvoline Full Synthetic 15W-40
• Valvoline Synthetic Blend 15W-40
• Valvoline All-Terrain 15W-40
• Schaeffer’s 15W-40
• Mobil Delvac Extreme 15W-40
• LIQUI MOLY Touring High Tech 15W-40
• Driven Racing Oil 15W-40
• Shell Rotella T6 Full Synthetic 15W-40
• Shell Rotella 15W-40