Description
Hamilton's flat tappet conversion kit comes with everything you need to eliminate the roller lifters and replace them with the much more reliable flat tappets that were used in Cummins engines prior to 2019. This kit has been designed to restore reliability and improve performance for the 2019-2024 6.7 Cummins engines.
This kit features new rocker arms with DLC coated trunnions, flat tappets and a 178/208 camshaft that has been designed to get the best efficiency out of daily driver and towing applications.
Owners report quicker spool up and throttle response, fuel economy gains and EGT reductions, all on stock vehicles with OEM tuning and all emission equipment present.
Forged steel camshaft. The 178/208 cams are forged, not cut from bar stock — producing a denser, more uniform grain structure. A natural “halo” forms on the exterior during forging, adding strength for extended service life.
DLC-coated tappets. Each tappet is gas carburized and polished to create a hard, stable base for the Diamond-Like Carbon (DLC) coating — an ultra-hard surface finish that dramatically reduces friction and wear.
Heavy-duty pushrods. Rated at 3,500+ lbs buckling force versus roughly 1,800 lbs for OEM, they drastically reduce deflection at high cylinder pressures and keep valve timing precisely in sync under load.
Upgraded rocker arms. High-quality casting built for intense heat cycles, with a gas-carburized ball and foot to reduce friction, and a DLC-coated trunnion that minimizes the galling common to OEM trunnions.
IMPORTANT NOTES:
Valve lash is to be set at .010" Intake & .020" Exhaust, set after 5 minutes of running then verify specs after retorquing the head.
Approved oil is required to ensure proper operation and longevity of this kit. Use a 15W-40 (or 5W-40 in sub zero conditions) with adequate zinc, phosphorus and molybdenum. This or low additive oils don't provide the shear strength a flat tappet needs and running a non approved oil will void the warranty.
High RPM (4,000+) and high spring pressures break through the oil film and degrade the DLC into graphite over time. Emissions-Compliant oils don't carry enough additive for these extremes. You can chase longevity or chase big power on this setup, but not both for long. Note that wear metals from any other failure can circulate in the unfiltered splash oil between the cam and lifters and can kill the coating quickly, so address any existing issues first.
Approved Oils:
- Valvoline Full Synthetic 15W-40
- Valvoline Synthetic Blend 15W-40
- Valvoline All Terrain 15W-40
- Shaeffer's 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
Hamilton prefers a Fleetguard Stratapore LF16035 oil filter, all warranty claims must include the failed parts with an oil sample, non approved oil will void the warranty.
Features & Benefits:
- Improved Reliability & Performance
- Replaces Lifters With DLC Coated Flat Tappets
- Includes Rocker Arm Assembly With DLC Coated Trunnions
- 178/208 Efficiency Camshaft For Daily Driving & Towing
- Fits The 2019-2024 6.7 Cummins