There Is A Genuine Difference When Replacing DPFs.

Cummins Genuine Diesel Particulate Filters.Cummins DPFs

When you’re faced with a cracked Diesel Particulate Filter (DPF) or one that’s beyond the point of cleaning and needs to be replaced - it’s important to know the difference between Genuine Cummins DPFs and DPFs that “will fit.”

Cummins recently conducted a competitive analysis of will-fit versus Genuine Cummins DPFs in vehicles equipped with 2007 ISX15 engines, under real-world operating conditions. The difference in performance was even greater than we anticipated.

Will-fit DPFs can create harmful levels of backpressure, hold less soot so they need more frequent regeneration, may not be cleaned completely and lack the proper amount of precious metal to enable catalytic reactions to take place. The results can be excessive fuel use, increased DEF use, potential turbo failures and additional triggering of fault code lamps and field service callouts.

To keep trucks running at optimum levels - long term or short term - the best choice is Cummins. And we have the test data to prove it.

Harmful Effects Of Higher Backpressure.

Higher-than-recommended backpressure can cause premature turbocharger wear and failure. It also can reduce an engine’s fuel economy, increasing operating costs.

The higher backpressure found in the will-fit DPF is due in part to a difference in filter cell wall thickness, cell density and wall pore size - all of which affect backpressure by limiting the Open Frontal Area (OFA) that exhaust gas flows through.

Critical Geometric Properties of Genuine Cummins DPFs.



Will-fit A

Will-fit B

Cell Density (cpsinominal+/-tolerance)

In Spec

Out of spec

Marginally in spec

Wall Thickness (milnominal+/-tolerance)

In Spec

Out of spec

Out of spec

Median Pore Size (MPSrange)

In Spec

Out of spec

Out of spec

OFA Estimate*


14% < baseline

7% < baseline

*OFA = Open frontal area. Baseline for genuine Cummins substrate material

Testing showed that the will-fit DPF demonstrated higher backpressure and reduced exhaust flow during real world operation when compared to the Genuine Cummins DPF.  

Will-fit DPF and Genuine Cummins DPF may look like they should hold the same amount of soot. However, the design and construction of the filter chambers are significantly different – at zero grams of soot loading you can see that the will-fit DPF produced more engine backpressure than the Genuine Cummins DPF.

The following chart illustrates the difference in backpressure and how it affects exhaust flow.
DPF Backpressure Chart

Lower Soot-Loading Capacity Leads To Excessive Regenerations.

As the chart below illustrates, the will-fit DPF tested triggered regenerations at just 40 grams while the Genuine Cummins DPF held up to 150 grams of soot before an active regeneration took place. That’s over 3.75 times the ash holding capacity.

Will-fit DPFs can nearly double the number of active regeneration events during normal operation. More frequent active regenerations result in worse fuel efficiency. Exhaust temperatures are being raised higher than 600° F twice as often - which can lead to both metal fatigue on the exhaust pipes and canister as well as increased risk of the DPF cracking and/or melting. Not to mention additional wear on other upstream engine components.
DPF Soot Loading Capacity Chart

Coming Clean: Where Will-fit DPFs Fail. Again.

Soot/ash accumulation in the aftertreatment DPF is a function of normal engine operation.  Over time, this accumulation can cause frequent aftertreatment regenerations. When a DPF fault code is registered, a restriction test is required to determine if the DPF needs to be cleaned. Before the test takes place, a stationary regeneration is conducted to remove soot present in the DPF. Our test data shows that, after a stationary regeneration, Genuine Cummins DPFs allow adequate exhaust flow - while will-fit DPFs still exceed the threshold for failure, requiring a time-consuming, costly field cleaning event.
DPF Field Cleaning Chart

Precious Metal Content Is Critical.

Having the right amount of precious metal content and correct distribution throughout the filter are critical. The will-fit DPFs tested did not meet Cummins standards - with significant consequences downstream in the SCR portion of the aftertreatment system including the potential to trigger fault code lamps, and increased consumption of Diesel Exhaust Fluid (DEF) in the SCR portion of the aftertreatment system.

A Minimum of $1,400 Saved In Total Cost of Operation.

Owners can plan on buying 2 will-fit DPFs versus 1 Genuine Cummins product. At today’s prices, that would cost about $3,400 versus $2,000 for the Genuine Cummins DPF. That’s roughly $1,400 extra for the DPFs alone. Downtime, missed deliveries, reduced fuel efficiency and labor costs all add even more.

ReCon DPFs.

For vehicles equipped with EPA 2010 and EPA 2012 Cummins ISX or ISL engines, an additional option to consider is the Cummins ReCon® DPF. It is rigorously cleaned and tested to meet Cummins specifications for soot capacity, proper exhaust flow, precious metal content and filter medium integrity. Yet, it costs approximately 40 percent less than a new, will-fit DPF. ReCon DPFs provide a highly effective and efficient solution that meets financial constraints while preserving Cummins performance and reliability.  For more information on Cummins ReCon DPFs, see ReCon Parts DPF Promo.

We’ve Got Your Back.

A product is only as good as the company that stands behind it. Not only do Genuine Cummins DPFs deliver unsurpassed quality - they’re backed by the largest and most capable parts and service network in North America with over 3,500 authorized locations. So no matter where the next load takes you, rest assured that there’s a nearby Cummins facility - and finding it is as easy as calling Cummins Care at 1-800-CUMMINS™ (1-800-486-6467), any time of the day or night.