6.7 Powerstroke vs 6.7 Cummins

The Ford 6.7 Powerstroke is a V8. The Ram 6.7 Cummins is an inline six. Both power heavy-duty trucks, but the right choice depends on the model year, the truck’s equipment and what you need it to do.

If you’re buying used, start with the service records and a thorough inspection. An engine badge alone won’t tell you how a truck has been maintained or what repairs it needs.

The main differences

The shared 6.7-liter size doesn’t make the engines interchangeable. Their parts, service procedures and truck applications differ. Even within one engine family, a kit for an early truck may not fit a later one.

Compare the exact model year

Power ratings, transmissions and engine hardware have changed over time. A comparison between a 2012 Ford and a 2012 Ram won’t answer the same questions as a comparison between two newer trucks.

High Output Cummins is one example. For 2021, Cummins offered the High Output version exclusively in the Ram 3500 with the Aisin transmission. For 2025, the new High Output diesel became available in both the Ram 2500 and 3500. Check the year and configuration before assuming that a 2500 has the standard-output engine or that every 3500 has High Output.

Which one is more reliable

There isn’t a useful blanket answer for every 6.7 Powerstroke and 6.7 Cummins ever built. Compare the specific trucks rather than treating every model year as the same engine.

For a used truck, ask for maintenance and repair records, then have a diesel shop inspect it before you buy. Pay particular attention to:

• Fuel-system maintenance and any previous fuel-system repairs.
• Coolant or oil leaks and any history of overheating.
• Warning lights, stored fault codes and the condition of the emissions equipment.
• Turbo, intercooler pipes, boots and clamps.
• Transmission operation and service history.

A list of common problems can help you decide what to inspect, but it doesn’t prove that one brand will cost less to own. For a closer look at used Rams, see our Cummins years buyer’s guide.

Towing and running costs

Compare the complete truck for the job you have in mind. The engine is only part of its towing capability. Cab and bed configuration, axle ratio, drivetrain, payload and hitch limits all matter.

Use the manufacturer’s towing information for the exact model year and configuration. Ford’s towing guides are a useful starting point for a Super Duty. Check the matching Ram owner’s manual and towing chart for a Ram.

Neither engine has one fuel-economy figure that applies to every truck. Trailer weight, speed, gearing, tires and driving conditions affect consumption. Avoid choosing between two trucks based on an MPG claim that doesn’t describe how it was measured.

Keep up with the basics

Follow the owner’s manual for your truck’s oil, fuel-filter, coolant and transmission service requirements. Use its instructions for the fuel-water separator and any emissions-system warnings. Service needs can differ with the model year and how the truck is used.

Check the charge-air hoses, pipes and clamps during routine inspections. If a boot is cracked or a connection is leaking, diagnose the problem before replacing parts. Our boost leak guide explains what to look for.

Mammoth kits for both engines

Choose by model year, engine and the application on the product page. This list covers the years stated in the linked listings; it doesn’t extend their fitment to newer trucks or other configurations.

• 2011–2016 Ford 6.7 Powerstroke: Polished intercooler pipe and silicone boot kit. The listing includes four aluminum pipe pieces, four silicone boots and eight constant-tension T-bolt clamps.
• 2007.5–2009 Ram 6.7 Cummins: Intercooler boot kit.
• 2010–2012 Ram 6.7 Cummins: Intercooler boot kit.
• 2013–2018 Ram 6.7 Cummins: Intercooler boot kit.
• 2019–2025 Ram 6.7 Cummins: Intercooler boot kit.

For more detail, read our 6.7 Cummins intercooler boots guide or Cummins radiator hose kit guide.

Review the lifetime limited warranty for coverage and exclusions. If your truck’s application is unclear, contact us with the year, model, engine and details of any changes to the intercooler piping before ordering.

Common questions

Is a Cummins a V8?

The 6.7 Cummins used in Ram Heavy Duty trucks is an inline six. The 6.7 Powerstroke used in Ford Super Duty trucks is a V8.

Does High Output always mean a Ram 3500?

No. The answer depends on the year. The 2025 Ram 2500 and 3500 both offered the new High Output Cummins diesel.

How does a 7.3 Powerstroke compare with a 6.7 Cummins?

That comparison involves trucks from different eras. Account for age, condition, equipment and repair needs rather than comparing engine names alone. Our 7.3 Powerstroke upgrades guide covers where to start on an older Ford.

Will new intercooler boots add horsepower?

Don’t choose replacement boots based on a promised horsepower gain. Repairing a boost leak can restore lost performance, but replacement boots alone don’t establish a horsepower gain on a healthy system. Match the replacement to the truck and address the cause of the failure.

Which should you choose

Choose the Ford or Ram that meets your towing and payload needs, has the equipment you want and passes a careful inspection. For used trucks, budget for the maintenance and repairs that the individual truck needs. Once you own it, order parts by its exact application rather than relying on the engine badge alone.