The pros and cons of removing your pickup’s DPF system
By Austin C. Craig
Ever since the first pickup was built owners have been trying to get more power and performance from their engines.
Today this is especially true of diesel pickups, as owners want increased performance and are always looking for ways to achieve their goals. Most diesel pickups are used for towing or carrying heavy loads, hence the desire for more horsepower, torque and performance.
The good news for pickup owners is that the performance aftermarket offers many ways and means to enhance performance.
With the advance in vehicle electronics, companies like Hypertech, SCT and H&S Performance offer programmers/ tuners that increase both horsepower and torque.
And if your goal is to maximize diesel engine power gained through electronic hot-rodding there’s only one more upgrade needed: remove any exhaust restrictions. Dump the Diesel Particulate Filter (DPF).
However, as all the aftermarket performance companies offering DPF Delete Kits are quick to point out, these kits are solely for closed-course racing and off-road use only and are not street legal in any state. It’s Federal law.
Get busted on a public road with the DPF removed and the owner of the pickup faces a $2,500 fine – and the installer who did the work faces a $25,000 fine as does the company who sold the DPF delete kit.
That’s why most manufacturers, dealers and installers of DPF delete kits require customers to sign a release clearly stating the product is to be used solely for competition and the owner of the pickup assumes all risk and liability if the product is used on public roads.
This little piece of paper provides them with a thin blanket of legal protection should Big Brother swing the big stick at a customer.
ABOUT DPF WARRANTY
Removing the DPF isn’t necessarily a power quest for owners of contracting businesses. It’s simply an easy “upgrade” to save money.
Some businesses feel it’s too expensive to replace the DPFs on older, high-mileage pickups that are losing power and fuel economy because the filters are plugged. (See “DPFs: Good As New” .)
As one contractor said, “It’s a whole lot easier for me to drop $300 on a DPF-delete kit than shell out $1,700 on a new DPF for a pickup that’s out of warranty.”
(Ford, Ram and GM warranty their exhaust’s smog components, of which the DPF is the main player, 100,000 miles or five years.)
In warranty or out, plugged up or open, it really doesn’t matter. The EPA mandates the DPF system be installed for the life for the vehicle.
DPF REMOVAL: PROS & CONS
No one disputes the DPF has an adverse effect on exhaust flow, although the newest generation of diesel pickups the exhaust restriction is far less noticeable.
Removing the DPF and running a straight-through exhaust from downpipe to tailpipe boosts power, considerably so when employing a power programmer that can alter the electronic engine controls to accommodate the higher air flow. It can also lower EGTs when towing.
The downside of deleting the DPF, aside from the legal pitfall, is getting rid of the pickup at the end of its company life cycle.
The dealers we talked with are quite strict about accepting trade-in pickups that have had the DPF systems removed. They don’t.
Federal law prohibits the operation, sale or lease or transfer of title of a light-duty truck (1975 or newer, 10,000 pounds gross vehicle weight or less) that has had the smog system altered or removed.
One Ford dealer principle we talked with said they make everyone who trades in a diesel pickup to sign a Vehicle Air Pollution Control Statement stating that the owner has not tampered with the air pollution emission control devices.
On top of that the dealership will not work on vehicles that have had their emissions equipment removed or modified.
In other words if the owner modifies a pickup and wants to sell it, they better sell it privately, but at a substantially lower price.
New owner vehicle registration is also a problem in states that require the owner to sign a registration form stating the emission controls have not been tampered with.
As a company owner, this has to be considered in the decision-making process related to removing the DPF.
Custom DPF-Delete Tuning
Owners who desire to eliminate the DPF system, after signing an acknowledgement of competition or “off-road” use and releasing the dealer/installer of risk and liability have a number of choices in how to maximize the power potential.
H&S Performance a variety of products that will increase the overall performance.
For example a Ford 6.4 liter Power Stroke equipped with an S&B cold air intake, DPF delete exhaust and their Black Maxx race tuner on “Hot” setting went from a stock 306 horsepower @648 ft-lb torque to 582 horsepower and a whopping 1287 ft-lb torque.
The GM 6.6 liter Duramax when equipped with and S&B cold air intake, DPF delete exhaust and a Black Maxx on the “Hot” setting went from a stock horsepower/torque rating of 290 HP/539 ft-lb torque to 446 horsepower and 845ft-lb torque.
A bone stock 2006 Cummins 5.9 liter equipped with a four-inch turbo back exhaust system and an H&S Mini Maxx on “Hot” setting went from 283 HP and 510 ft-lb torque to an impressive 482 horsepower and 1028 ft-lb torque.
There are several other manufacturers of electronic hot-rodding products that report similar performance gains.
We talked to a number of pickup owners who have kept their DPF systems and have chosen legal ways to increase their diesel’s performance.
These include upgrades from simple DPF-back exhausts and cold-air intakes to programmers and computers that will change the power curve.
Hypertech offers a number of performance tuners for the Chevrolet Silverado 3500 6.6L V8 diesel. A good example is the Hypertech Max Energy Power Programmer for a 2005 Silverado equipped with the Duramax 6.6L that brings another 87hp and 173 ft-lb torque to the table.
H&S offers tuning that bumps Ford, GM and Ram diesels 40 to 175hp with stock intake and exhaust.
The folks at SCT Tuning also offer a wide variety of programmers for use with a DPF system. For example, the SCT Livewire flash tuner dyno results show that on a 2003-2004 6.0L Ford Power Stroke horsepower increased by an average 150 rear wheel horsepower with a ft-lbs torque gain of 290.
These are but a few examples of what is available to owners of diesel powered pickup owners today.
In addition to tuners, there are performance intake and exhaust products from any number of manufacturers to meet and satisfy increased performance demands for just about any application.
THE BRIGHT SIDE
The good news is that there are many ways to increase the power and performance of diesel pickups without breaking the law.
With proper maintenance the DPF systems will work properly for many years past the manufacturer’s warranty.
The DPF filters are available from the manufacturers as well as aftermarket companies like Econix and Cleaire and run around $2,500.00 for the filter, sensors and labor.
Remember it is against the law and the EPA can and will come after anyone who physically alters the DPF-federally mandated emission system on their pickup.
H & S Performance ; www.hsperformance.com
MBRP Performance Exhaust; www.mbrp.com
SCT Performance ; www.sctflash.com