However, something spectacular happened and the complete opposite thing occurred. It turns out that Americans truly do adapt and overcome. Every one of the manufacturers figured out a way to cut down on the NOx levels all the while making more horsepower and torque than ever before.
Innovation is bread out of strife. The engineering breakthrough came through the use of the selective catalytic reduction. The vast majority of these systems use diesel exhaust fluid mixture of urea and deionized water sprayed into the exhaust system to break down the generated NOx into harmless nitrogen and water molecules. Since the DEF Diesel Exhaust Fluid is introduced in the exhaust, also called after-treatment technology, the manufacturer is free to build as much power as they want.
The DEF is stored in a separate tank which is insulated and heated and is marked by a blue filler cap. Still there are two factions of diesel guys out there; those who have accepted to the EPA changes and those who are still vehemently against any regulations whatsoever despite the work around technological advancements. For those not willing to accept the changes there has been a shift to older used diesel engines or remanufactured diesel engines that have been grandfathered in.
This article aims to go over the cold hard facts about DEF and educate the populace into making smarter diesel operator decisions. From a strictly chemical disposition DEF is a mixture of Urea is a compound in Nitrogen that turns to ammonia when heated and is used in a variety of industries. Urea is technically derived from a byproduct of urine but for mass production purposes it is synthetically made. Lets take a look at the science behind DEF when mixed with exhaust.
Chemically, DEF is firstly comprised of NH2 2CO; and when injected into the hot exhaust gas the water evaporates leaving ammonia and isocyanic acid. That question specifically depends on miles per gallon and usage of the diesel truck in question. No matter how heavy the load, according to the OE manufacturer, the typical average light duty truck will consume gallons of DEF per miles.
For every 50 gallons of diesel fuel burned you will use 1 gallon of DEF. DEF is mostly sold at truck stops in big jugs containing multiple gallons of the stuff. We have also compiled a list of the most popular manufactures of DEF here. There are very few cons with DEF as it is a fairly simple procedure to deal with.
These systems are complicated in design and a simple clogged filter can cause pressure and temperature differentials that can affect the whole performance of the engine. The only cons to DEF include the additional upfront cost to the truck, added nominal weight and some additional room to store an extra gallon of the fluid. The pros are better fuel economy, increased horsepower, more optimized combustion, fewer regenerations issues, less wear on the engine and in addition it only releases nitrogen and water vapor into the air.
Whether it is a big deal or not is not really not up for debate considering all light-medium diesel and up have to comply with the EPA Regulations. While the thawing process is taking place the vehicle's performance will not be affected the amount of DEF used will be reduced because a cold engine produces a low level of NOx emissions. In some cases the DEF supply tubes are also heated to prevent freezing or tubes are emptied once the engine is turned off. In short, there is no reason to be concerned about using your SCR truck in cold weather.
Diesel Exhaust Fluid DEF evaporates if stored at higher temperatures for a prolonged period because it is To avoid any risk of evaporation keep the cap of the DEF tank and storage containers securely closed. Field tests have shown that even in high temperatures there is no significant risk evaporation from DEF tanks.
Diesel Exhaust Fluid DEF uses automotive-grade urea which has a much higher purity than fertilizer urea. Using a lower-quality fertilizer urea will cause degradation of the Selective Catalytic Reduction SCR system, eventually causing the truck to break down. In the short-term it may also cause the sensors to believe the truck's DEF tank is empty and prompt a de-rating event, which reduces engine power and eventually prevents the engine from restarting.
If ingested, a physician should be consulted immediately. Under normal conditions of use, inhalation is not expected. If you do inhale these fumes from DEF, move to an area of fresh air. A physician should be consulted if you experience any continued symptoms, such as irritation to nose or throat. DEF does sometimes have a slight ammonia smell similar to home cleaning agents , but these are not harmful.
Do I need to wear protective clothing when filling up the DEF tank? What should I do if a spill DEF? Does DEF evaporate, and what happens if it does?
Fuel is squirted into the hot exhaust and burns, quickly raising temperatures in the catalysts. The cooled gases have a higher heat capacity and contain less oxygen than air, lowering combustion temperatures and reducing the formation of NOx. Power ratings play a role in how much emissions equipment is needed.
We think there will be a significant power bump when the final numbers are revealed. It also has a smaller radiator and cooling system.
Efficiency improvements to the recirculation system include new separate cold and hot circuits that allow exhaust gas to recirculate immediately after engine startup, when engine temperatures are still relatively cool and when the engine is idling. Fuel pressures are up from 1, bar 26, psi to 2, bar 29, psi for improved fuel atomization and combustion control. The new Duramax keeps the same Garrett-supplied single turbo setup of the LMM Duramax, though the compressor and turbine wheel diameters and blade trims have changed.
Combined with a new pre-combustion fuel-injection scheme that injects two pilot injections into the cylinder before the main injection, noise levels have been reduced up to 50 percent in the 1,, rpm peak torque operating range.
Arvan said the van we drove was pre-production and only about three-quarters of the way through finalizing its engine calibrations. Another change is reduced engine-idle speed. The van is able to idle at only rpm. All new engine controllers are needed to manage the sophisticated fuel and emissions system.
Arvan says they have twice the number of calibrations as the previous LMM diesel to help the engine run as efficiently as possible across the widest range of operating conditions.
The oil pump is slightly bigger, plus there have been some minor changes to the crankshaft and pistons. Aluminum heads — a Duramax hallmark — remain. Engine weight is said to be comparable to the LMM engine. Arvan also says fuel economy will remain the same — a key concern of any new diesel owner given the emphasis on clean emissions over operating efficiency. Enter your email address to subscribe to this blog and receive notifications of new posts by email. Email Address:.
Sign me up! Tag Archives: urea February 16, By davisgmcbuick. The enhanced, legendary Duramax 6. This proven powerplant gets the job done while being friendlier to the environment. DEF is used with diesel engine exhaust systems to reduce the amount of emissions produced by turning Nitrogen Oxide NOx into nitrogen and water vapor. DEF technology has a proven track record since it has been used in Europe for years.
A full tank of DEF provides a driving range of about 8, km. Since DEF is directly related to fuel consumption, range will vary depending on driving conditions. DEF is stored in a 5. The DEF tank fill point is conveniently located under the hood, along with other fluids that require periodic maintenance.
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