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Badlionsfan
| | Posted on Monday, January 26, 2015 - 06:28 pm: | 
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DEF itself is no big deal. The system can be a nightmare tho. DEF system issues have caused more downtime than every other thing on the trucks combined. That's 8 trucks at our terminal that were out in service late spring or early summer 2012. |
7873jake
| | Posted on Monday, January 26, 2015 - 08:33 pm: |
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So Ive been enjoying the TDI part of "der vagen" (if that means something bad in German, my apologies) quite a bit but also REALLY enjoy the level of comfort and quiet this thing exudes on the road. I'm 6'3" and 240#'s (225-230 when I go to Kuwait and catch some vicious respiratory illness but that's for another day).
We have a couple of M-B/Freightliner Sprinters in our fleet and routinely get new ones through, upon which new projects are built. I've always enjoyed their woooosh of torque and the fluidity with which they move through traffic, even the 3500 Series (dually) units but am enjoying the car more.
DEF systems in and of themselves aren't entirely the spawn of the devil, per se. I'm used to the world of DEF as our larger trucks are DEF dependent EXCEPT for the horrid and utterly disappointing Navistar International Maxxforce units, circa 2010-2012, that can't go down the road without a blown radiator hose, abysmal loss of power and/or melting of plastics under the hood.
While the amount of ink spent on writing about them is probably measured in gallons at this point, their never ending cost of ownership for some of our customers is downright disgusting. I told one International sales guy to stop telling people the non-SCR chassis were made in the USA as it was an embarrassment to people who actually build something worth a damn in this country. He said "well, they are made in Mexico actually." I said, "well don't offend Mexico by saying these are built there either!"
Sorry for the soapbox but I **really** hate any International non-SCR truck (but love the hell out of my TDI). I will make an empirical observation about our larger trucks...the Freightliner M2 series we build on rarely encounter the leaks, issues and repair bills that our International customers report battling.
If you want a good read, track federal grant money to Navistar/International, the fines they should have faced for their non-SCR, non-EPA compliant approach to diesel engines and relationships with Rahm Emanuel. I'm not a conspiracy theorist but how they've continued to survive defies the odds. |
Ratbuell
| | Posted on Monday, January 26, 2015 - 08:35 pm: |
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What sort of failures are you experiencing? I've had my JGC out in all weather, all conditions, zero issues despite many forum claims ("it's on the internet so it must be true") of injector issues, sensor issues, etc. I don't dilute or try and cheat the system, and like I said...I've only had to fill the tank one time in 10k miles. Operating temps (and storage temps) for the vehicle range from 100F down to 0F thus far. |
Badlionsfan
| | Posted on Monday, January 26, 2015 - 10:23 pm: |
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We've had several issues with sensors going bad, a few trucks keep having pump issues, wiring problems, etc. It seems like if you get a good one (like the one I'm assigned has been) it stays good. The ones with the biggest issues seem to be repeat offenders for the same thing. The bad thing is no one really knows how to troubleshoot these systems yet. All they do is read codes and throw parts at it til the problem goes away.
I will agree that those internationals were garbage. I don't buy into the conspiracies about them tho. Their plan was to crank up the % of EGR, while everyone else was able to back off on the EGR % thanks to SCR. International thought they'd sell to fleets who didn't wanna deal with DEF. It failed as badly as I expected it would. |
Badlionsfan
| | Posted on Monday, January 26, 2015 - 10:25 pm: |
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Btw, our trucks use around 20 gallons of DEF a week. Some more, some less. |
7873jake
| | Posted on Monday, January 26, 2015 - 10:43 pm: |
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20 GALLONS A WEEK!!!??? 
We might buy 20 gallons a year. Most trucks come in with 75% or more in the tank from the MFG. Since we spend more time building them than driving them (build time ranges from 6 months to a year), our only real problem is keeping the fuel tanks clean. Last year, I had one truck whose mileage I could measure with a tape measure.
(Message edited by 7873jake on January 26, 2015) |
Ratbuell
| | Posted on Monday, January 26, 2015 - 10:47 pm: |
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damn, that's some consumption! What sort of miles are you talking per week?
The issue with SCR is added weight, added heat, and added component stress (along with decreased HP/tq). We went through it in the RV chassis industry, too. SCR "sounded good", but made engines heavier, reduced power, increased heat, required additional heat exchangers...DEF (to me, at least) seems a natural answer. No changes to the powerplant itself, just change the downstream exhaust gasses.
Like I said - I love my no-DEF, no-cat, no DPF, 01 Ram's exhaust 'scent'. No tuners, no black smoke BS, just a stock truck with a cold air intake and Banks 4" exhaust. That said, though...I definitely appreciate the "hey mister, you're at a diesel pump, STOP!!!" aspect of my nice, quiet, no-smell Jeep diesel with DEF system  |
Badlionsfan
| | Posted on Monday, January 26, 2015 - 10:48 pm: |
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What kind of trucks?
I'm talking about class 8 Mack trucks, that see 3500 miles plus a week. |
Ratbuell
| | Posted on Monday, January 26, 2015 - 10:52 pm: |
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I'd have to do some research, but that still sounds like high consumption. I'm 3.0L engine displacement, and an 8 gal DEF tank has gotten me 10k+ miles. Granted...I don't tow, or "work it hard", but damn - is that what heavy trucks use? Even so, though, I'd have to take it as the option over SCR maintenance and component replacement. Especially with the convenience of at-the-pump fillups. |
7873jake
| | Posted on Monday, January 26, 2015 - 10:55 pm: |
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Mostly Freightliner M2 106 and 112 up to 54k lbs with custom built bodies with LOA of 45' or less. Not all are class 8 but some are.
We build on any chassis the customer wants, including export (high sulfur) Internationals, Freightliners, Macks and Peterbuilts. Rarely on MAN chassis but if you want something on one, we'll look at it and give you an engineering review. Have built satellite trucks for Africa on MANs in the distant past.
Also work on Sprinters, Suburbans, F-series chassis and trailers.
http://www.MBFindustries.com |
Badlionsfan
| | Posted on Tuesday, January 27, 2015 - 01:16 am: |
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From www.discoverdef.com
How much Diesel Exhaust Fluid (DEF) will my truck consume?
"Diesel Exhaust Fluid (DEF) consumption is measured as a ratio of diesel fuel use, normally termed the "dosing rate" or "treat rate". Medium- and heavy-duty vehicles have a dosing rate of 2-3%. This means that if your truck has a fuel efficiency of six miles per gallon and a dosing rate of 3% it will use approximately 1 gallon of DEF every 200 miles.
Feedback from a number of fleets suggests that the dosing rate is slightly lower than originally predicted by manufacturers, at around 2.0-2.5%."
Based on this (I get right around 6mpg average on my truck combined between the highway miles I put on it and the city driving it does during the day) at 3500 miles a week total it should be around 17.5 gallons per week. I don't know the exact usage because we never let it get lower than 1/4 tank indicated on the gauge and our pump doesn't have a meter. We have a 275 gallon tote with an electric pump at our terminal that gets filled by a bulk delivery company. |
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