What if someone could think up a way to turn the sooty exhaust from diesel vehicles into harmless air? That would be a win-win for both drivers and breathers. Actually, some very smart people have thought up a clever way to clean up diesel exhaust, and vehicles are using this method on the roadways today.
If you have a truck or other vehicle with a diesel engine, you may already be familiar with the technologies of selective catalytic reduction (SCR) and diesel exhaust fluid (DEF). If you’ve recently bought a late-model diesel vehicle, this dual exhaust-cleaning system may be new and strange to you.
In either case, you should know that without proper maintenance, your SCR system will disable your vehicle. Follow the tips below to manage your vehicle’s SCR emissions system.
Keep Track of Your DEF Usage
New diesel SCR systems are designed to take the particulate matter out of dirty diesel exhaust by means of special filters. A secondary method of exhaust “treatment” occurs when DEF, a special urea/ionized water mixture, is spritzed on exhaust fumes in a closed chamber. The DEF helps turn all of the smog-producing molecules in the diesel exhaust into harmless water vapor, nitrogen and carbon dioxide.
DEF is stored and dispensed from a reservoir located somewhere under your hood or near the gas tank. You’re responsible for keeping tabs on the level of DEF in your vehicle. The amount you use will vary depending on the type of engine you have and the way you drive. Some vehicles get 1,000 miles to a gallon of DEF, while other vehicles doing heavy towing or mountain driving will use more of the fluid.
Dry, hot road conditions tend to increase DEF usage according to experts. If you drive in cooler, more humid conditions, you can expect to use less DEF. Keep track of your usage for the first few tanks of DEF to determine how often you can expect to refill the reservoir. The refill port on the DEF is smaller than a standard diesel port to help avoid confusion when refilling the DEF tank.
Pay Attention to the Warnings
Manufacturers equip DEF-outfitted vehicles with warning systems that give you plenty of advance notice of a pending empty DEF tank. Each vehicle’s warning system is different, but most will alert you to the fact that you won’t be able to start your vehicle again until you refill the DEF reservoir.
If you’re driving when the warning occurs, don’t turn off the engine until you’re in a location where you can source DEF. The warnings tell the truth—your truck won’t start without it. Other vehicles may slow to a crawl when the DEF tank runs out. Your diesel mechanic can explain what will happen to your vehicle if you fail to heed the low-DEF caution lights.
Aside from harming the environment, you risk harming your vehicle when you don’t maintain your SCR system. Pay attention to all of your diesel engine’s filters and fluids to make sure the fuel and air quality in your diesel ride are always clean.
Handle DEF with Care
DEF is extremely easy to contaminate. It only takes a tenth of a teaspoon of known contaminants, like aluminum or zinc, to ruin 5,000 gallons of DEF. Never pour DEF from a fresh container into any other container or into a dirty funnel.
DEF comes in a solution that does not need to be mixed at all but does need to be protected from coming into contact with any sort of oil, debris or other substance. Refill your DEF tank in a dry, clean and dust-free environment. Cap both the container and the reservoir as soon as possible after filling.
DEF will congeal when it freezes, which occurs at temperatures around 12 degrees. The DEF containers you buy at the store will have extra room for the expanding fluid. Always let the frozen DEF warm up before adding it to your system.
Contact the diesel experts at Powerstroke Performance and Repair, LLC today to learn more about your Ford’s SCR and DEF systems. Our certified techs perform professional, expert repairs on Ford diesel trucks in Hampton Roads.