Hamilton Cams 2025+ Ram 2500/3500 6.7L Cummins Flat Tappet Conversion Kit
Can I pick up my order or have it installed at your shop?
Can I pick up my order or have it installed at your shop?
Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at 636-429-7020 or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.
How do I know if this part fits my vehicle?
How do I know if this part fits my vehicle?
Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.
What if I need to return a product or it’s defective?
What if I need to return a product or it’s defective?
Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)
What's the lead time on custom or fabricated parts?
What's the lead time on custom or fabricated parts?
Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at 636-429-7020 and we’ll confirm current availability or estimated ship dates.
Flat tappet conversion kit for the 2025–2026 Cummins, with a forged steel camshaft, DLC-coated tappets, pushrods and upgraded rocker arms. Contact us before ordering if the head or block has been surfaced, and review the oil, RPM and installation requirements below.
Backorder availability: December 1, 2026.
Hamilton Cams Complete Kit for Cummins Engines
Strength, durability, and precision—those are the hallmarks of our Hamilton Cams flat tappet conversion kit™. From forged steel camshafts to DLC-coated tappets and robust pushrods, every component is engineered for performance and reliability. Trust in our decades of research, thousands of dyno tests, and millions of real-world miles to deliver a kit that stands the test of time.
“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 denser, more uniform grain structure.
- Enhanced Longevity: A natural “halo” in grain structure forms on the exterior of the cam during forging, adding strength for extended service life.
DLC-Coated Tappets
- Gas Carburized & Polished: Each tappet undergoes a hardening process that provides a stable base metal for the DLC coating.
- Diamond-Like Carbon (DLC) Coating: This ultra-hard surface finish reduces friction and wear. Incorrect oil, incorrect lash, valve float, or metal contamination can damage the coating.
Valve Lash & Operating Requirements
Lash that is too loose can damage the tappets or coating by increasing impact when the clearance is taken up. Lash that is too tight can damage the coating by preventing adequate oil film formation before the next impact cycle.
- Intake Valve Lash: 0.010″
- Exhaust Valve Lash: 0.020″
- Check valve lash after five minutes of running, and recheck after retorquing the cylinder head.
High RPM amplifies the impact between the camshaft and tappet. Operation above 4,000 RPM and high spring pressures are discouraged for longevity. Although this is a performance camshaft that is emission compliant, think of it as a fix for stock or mild builds that do not exceed 4,000 RPM and use OEM springs.
When oil viscosity is too low, lash is excessive, RPM is too high, or spring pressure is too high, the oil film may not adequately separate the tappet and camshaft. Under these conditions, the DLC coating can degrade and delaminate.
Wear metals from other engine failures can enter the non-filtered splash oil and damage the DLC coating. Clean oil and proper filtration are essential.
Heavy-Duty Pushrods
- 3,500+ lbs Buckling Force: Compared to around 1,800 lbs for OEM pushrods, ours reduce deflection at high cylinder pressures.
- Consistent Valve Timing: With less flex, your valvetrain stays precisely in sync—even under demanding 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.
Important Fitment Notice
If you have had your engine block or cylinder head surfaced, please call us for verification to ensure proper kit fitment.
Oil Requirements & Warranty
Approved oil is required. Use an approved 15W-40 oil for normal temperatures, or an approved 5W-40 oil for sub-zero Fahrenheit conditions. The oil must provide adequate zinc, phosphorus, and molybdenum for flat tappet operation.
Thin or low-additive oils may not provide the protection a flat tappet requires. If you need a 5W-40 oil for sub-zero conditions, contact Hamilton Cams to confirm the specific oil is approved before use.
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
- Redline 15W-40
Acceptable Oils
- Shell Rotella T6 Full Synthetic 15W-40
- Shell Rotella T5 15W-40
Preferred Oil Filter: Fleetguard Stratapore LF16035.
Running a non-approved oil voids the warranty. All warranty claims must include the failed parts and an oil sample.
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.
When you choose Hamilton Cams, you are investing in proven innovation and superior craftsmanship. Help your Cummins engine deliver reliable power for the long haul with a kit designed for durability when installed and operated within the requirements above.
This part fits the following vehicles:
| Years | Make & Model |
|---|---|
| 2025 | Ram 2500 |
| 2025 | Ram 3500 |
Fitment is listed by year, make and model. Some applications also depend on cab, bed, drivetrain or engine — if you are not sure, call 636-429-7020 or send us your vehicle details and we will confirm before you order.
