New Rigs- DEF

[baraff]

I'm beginning to think that older diesel rigs that don't use this nanny-state technology may actually appreciate in value.

[pagosajoe]

Originally Posted by 450Donn

I stand corrected. This from discover DEF.com

What will happen if my truck runs out of Diesel Exhaust Fluid (DEF)?


The EPA requires vehicle manufacturers to put measures in place to ensure that vehicles cannot run without DEF. Most manufacturers have approached this in a similar way. Before a truck's DEF tank runs empty the driver is given a series of alerts on their dashboard displays (much the same way as if they were running low on diesel). Generally speaking, when the DEF tank level drops below 10% an amber warning lamp will come on, at 5% this lamp starts flashing and below 2.5% a solid amber warning light is displayed.
If the truck is allowed to run out of DEF completely, the engine's power is reduced. This generally follows the next intentional key-off, when vehicle speed will be limited to 5 mph and a solid red warning will be displayed.


I guess it does not completely shut down. But limiting to 5MPH is as good as in my book.

Yeah, they want you to be able to get to a DEF pump/source to fill up again.

Cheers,

Joe

[djbmsu]

I have the DEF on our new Allegro RED and thought some many be interested in two comments. My wifes parents parked their 2005 Dynasty cummins, pre DEF in our back yard and the exhaust was within about 5 feet of a planter with various plants that eventually died from the running of the Dynasty exhaust. Since they sold the Dynasty we moved our new RED into where they used to park and within the same distance as the newly replanted pot, with the same plants. We run our Diesel the same as they did prior to leaving and when returning and strangely the plants have not shown any wilting or dying from the fumes. Interesting to me at least. Secondly I have scouted prices for the DEF at numerous places from Wal Mart to auto stores to gas stations to flying J and others. Wal Mart has always had the best prices from 10.99 to 11.95 just in case you're looking.

[mhs4771]

Originally Posted by K-Star

In the first years of the Diesel Particulate Filter (DPF), many manufacturers used raw diesel fuel to clean (regen) the filter by burning it in the filter to eliminate particulates that are trapped. This contributed to poor fuel mileage in those models. About 2 years ago a lot of them started putting a separate tank in for Diesel Exhaust Fluid (DEF) which is burned in the DEF in the regen process rather than raw fuel. This helps improve the poor fuel mileage of the earlier models. DEF can also be pruchased in 2.5 gallon bottles in truck stops, auto parts stores and WalMart for around 15 bucks.

K-Star, you're a little off base with your reply. DEF and DPF are two different systems, but the newer trucks generally have both (I'm only sure about GM). DEF is internally mixed with Fuel (at a predetermined rate based on fuel flow) to allow the SCR to reduce the NOX level. The DPF still traps soot particles and now instead of flooding the engine with raw fuel, fuel is injected directly into the DPF where the temps are high enough to ignite the fuel and burn off the soot, called the Regen Process.

[dieselclacker]

Just curious, is the cost of DEF figured in when checking the MPG on a coach that is required to use it? Or, is MPG even a concern for owners of coaches that require it? Does the claimed increased MPG on DEF equipped coaches cover the cost of the DEF? Not trying to be a smartass here, just curious to know.

[BCooke]

http://www.folsomlakefordfleet.com/t...scranddpf.html
Has a descent description of the Ford 6.7 system.

[450Donn]

Originally Posted by dieselclacker

Just curious, is the cost of DEF figured in when checking the MPG on a coach that is required to use it? Or, is MPG even a concern for owners of coaches that require it? Does the claimed increased MPG on DEF equipped coaches cover the cost of the DEF? Not trying to be a smartass here, just curious to know.

Most people don't add the cost of the DEF to the cost of their fuel bill. General consensus is that it adds approx $0.001 to the cost per gallon of diesel. So far from what I have read with new trucks pulling large trailers/fivers the claimed improvement in fuel economy is just not there. Most DEF people still claim about 10MPG towing, which is what I can get with my Cummins without DEF.

[BCooke]

Originally Posted by 450Donn

Most people don't add the cost of the DEF to the cost of their fuel bill. General consensus is that it adds approx $0.001 to the cost per gallon of diesel. So far from what I have read with new trucks pulling large trailers/fivers the claimed improvement in fuel economy is just not there. Most DEF people still claim about 10MPG towing, which is what I can get with my Cummins without DEF.

Just out of curiosity how heavy is your unit. I have noticed about a .5 MPG hit if I am running fully loaded ~14k versus a light trip ~10k. (Ford 6.7)

[450Donn]

Originally Posted by BCooke

Just out of curiosity how heavy is your unit. I have noticed about a .5 MPG hit if I am running fully loaded ~14k versus a light trip ~10k. (Ford 6.7)

Last scaling, 11,000 truck 13,500 trailer. I have run at those weights for the last couple of years give or take a few pounds. Two different trips over the mountains to the coast I got 10.5 going and 11.5 coming back. I generally run 55-60 over the Cascades to Central Oregon and get 9.5-10.5. But that's going from basically 500 feet to over 4000 feet in elevation, with two pretty good climbs thrown in for good measure.

[Roam America]

the new Ford motors go into "limp mode". not sure what happens if the user does not respond to that timely fashion.

[Roam America]

Originally Posted by mhs4771

K-Star, you're a little off base with your reply. DEF and DPF are two different systems, but the newer trucks generally have both (I'm only sure about GM). DEF is internally mixed with Fuel (at a predetermined rate based on fuel flow) to allow the SCR to reduce the NOX level. The DPF still traps soot particles and now instead of flooding the engine with raw fuel, fuel is injected directly into the DPF where the temps are high enough to ignite the fuel and burn off the soot, called the Regen Process.

i wasn't trying to imply they were the same. maybe my wording wasn't the bets. i did not know it was mixed with the fuel. for that i stand corrected.

if we do not continually learn we become stagnant.

[BCooke]

Originally Posted by K-Star

the new Ford motors go into "limp mode". not sure what happens if the user does not respond to that timely fashion.

Keep in mind I do not read the manuals, normally.
I think you get warning... you get a speed limit warning in xx miles... at some point it will not let you drive it, it will only idle.

[richardcoxid]

450Donn

According to your previous post the cost of DEF add about $0.001 to the cost of a gallon of Diesel. If my mental gymnastics is correct, you are saying that ONE THOUSANDTH of a dollar which is ONE TENTH of a cent added to the cost of a gallon of Diesel. Am I misplacing a decimal point or zero?

[JMonroe]

I've found the Cummins estimate of 2% DEF usage to diesel to be pretty accurate. In fact, I'm using a bit less DEF than that estimate. At 8 mpg and $4 per gallon of fuel you'd be using about $200 of fuel to go 400 miles. Purchased in 2.5 gallon jugs you can easily find DEF at under $12 for that jug, or about $4.80 per gallon. You're adding just under 10 cents per gallon of fuel at these conservative numbers, or just over one cent per mile.