New to Me 4th Gen

[JR]

Another concern of buying bulk at stations is product contamination which happens a lot!! Not so much by hooking up the unloading hose to the wrong product tank (I believe they are different size hoses to prevent this) but from what was hauled in the truck tank before DEF was loaded. I don't know for sure but I would almost bet that the truck isn't exclusively DEF product only? During my driving career we had charts that were STRICTLY adheared to, to prevent product contamination especially Jet fuel. I have a call in to a friend thats still in the industry to address this question.

It would be interesting to know how long bulk sits between deliveries, how and where it is stored, etc.

 

[kthaxton]

I have been told the new 1K Cummins uses A LOT more DEF. I guess turning up the wick means more cleanup.

I have my doubts. I suspect the only way they would use more DEF is if they were working it harder (because they can) than they would a truck with less output.

For example, say there is a grade that a person travels frequently. Towing up this grade with a previous truck of 900 ft/lbs this truck was only capable of achieving 55 mph. Now, this person has a new 1000 ft/lb truck and can now go 60 mph up this grade......this scenario would use more DEF (and fuel) because the extra engine output is being utilized. Under normal driving conditions, it is not.

Contrary to popular belief, a vehicle is not constantly driving around putting out its peak torque. It takes X amount of torque to move X amount of weight a given speed. If it puts out more torque than that, you will go faster. If you intend to maintain a certain speed, any additional torque your engine is capable of producing beyond what it takes to maintain that speed, will not be produced.

I suppose there is the possibility of a new emission strategy that would increase the dose of DEF, but I'm fairly certain that the optimal dose was determined quite some time ago and any more than that would be a waste.

 

[TFucili]

I have my doubts. I suspect the only way they would use more DEF is if they were working it harder (because they can) than they would a truck with less output.

For example, say there is a grade that a person travels frequently. Towing up this grade with a previous truck of 900 ft/lbs this truck was only capable of achieving 55 mph. Now, this person has a new 1000 ft/lb truck and can now go 60 mph up this grade......this scenario would use more DEF (and fuel) because the extra engine output is being utilized. Under normal driving conditions, it is not.

Contrary to popular belief, a vehicle is not constantly driving around putting out its peak torque. It takes X amount of torque to move X amount of weight a given speed. If it puts out more torque than that, you will go faster. If you intend to maintain a certain speed, any additional torque your engine is capable of producing beyond what it takes to maintain that speed, will not be produced.

I suppose there is the possibility of a new emission strategy that would increase the dose of DEF, but I'm fairly certain that the optimal dose was determined quite some time ago and any more than that would be a waste.

My buddy has a 2019 3500 SRW. He is retired, and not a Ricky-Racer type, and he was the first to tell me he noticed a difference. His previous pickup was a '16(?) six speed. He also has a deleted dually flatbed that I believe is an '07(?). Time will tell.

 

[Newsa]

I have been told the new 1K Cummins uses A LOT more DEF. I guess turning up the wick means more cleanup.

IDK about alot. Definately will use SOME more due to higher cylinder pressures and resulting combustion temps from that higher pressure. CGI is advertised to hold higher pressures. Probably stronger head bolts. Definately higher output turbo.

 

[AH64ID]

If the 19's use more DEF I would guess it's due to tuning and running slightly higher combustion temps and pressures, thus making more NOx and needing more DEF. So DEF percentage might be up, and fuel use might be down.

The power ratings are so similar that most probably won't notice a difference.

 

[Wayne M.]

I know there’s a relation between DEF usage and EGR. Less EGR blend = more DEF needed to control NOx. I know there’s a move to get away from EGR via better fuel charge management and such.

 

[TFucili]

If the 19's use more DEF I would guess it's due to tuning and running slightly higher combustion temps and pressures, thus making more NOx and needing more DEF. So DEF percentage might be up, and fuel use might be down.

The power ratings are so similar that most probably won't notice a difference.

Yup, like I said, when you turn up the wick there is more to clean up.

 

[AH64ID]

Yup, like I said, when you turn up the wick there is more to clean up.

Except a SO 19 is rated lower than a HO 18.

Do the 13-18 Aisin's burn more DEF (as a percentage) than 68RFE's?

 

[Newsa]

Yup, like I said, when you turn up the wick there is more to clean up.

NOx comes from atmospheric nitrogen. Not directly from fuel. It might use more fuel depending on tuning. The higher pressure turbo could be contributing partly to higher cylinder pressure. Maybe there is also higher efficiency?

Edit. The turbo will be the same for SO and HO. Looks like the programming for the turbo helps determine how vigorously it operates along with the programming for the fuel injection.

 

[Wayne M.]

I thought NOx was a byproduct of the conditions of combustion, namely the cylinder temp during combustion. That’s the whole purpose of EGR, is to reduce the oxygen and thus the potential combustion temp. With SCR, less EGR is needed and NOx can now be allowed to happen because it’ll be taken care of by SCR.
That’s the main reason for the better fuel economy on the SCR trucks.

 

[Newsa]

I thought NOx was a byproduct of the conditions of combustion, namely the cylinder temp during combustion. That’s the whole purpose of EGR, is to reduce the oxygen and thus the potential combustion temp. With SCR, less EGR is needed and NOx can now be allowed to happen because it’ll be taken care of by SCR.
That’s the main reason for the better fuel economy on the SCR trucks.

It is a function of temp and pressure. The atmospheric nitrogen combined with oxygen is what produces NOx. It requires high pressure/temps to form it. But how much of that temp pressure increase is due to fuel and how much is due to forced air induction is uncertain. I would guess that if the 13-18' use 2.5% def to fuel ratio, the 19's use 3%+ def to fuel ratio? I have seen reports of other engines using anywhere from 2% def to 5% def. I believe that is the difference between a variety of different engine conditions that cause various cylinder temps/pressures

 

[TCDiesel]

The Exhaust gases are use to lower Flame Temps Like Wayne M mentioned. The bigger displacement engines create less NOx BC its not necessary to increase boost to create HP, That's Why Smaller displacement engines use so much EGR, they are constantly in higher boost conditions to create the HP, The VM 3.0 is absolutely a EGR cluster fudge it always under (High) boost increasing the cylinder pressures increases the heat/flame during combustion that creates the NOx.

 

[BIGNASTY]

Got an answer to a question posed to a buddy. It seems as if most all of the trucks that haul DEF are exclusive use trucks for the simple fact that washing out the product from the load before loading DEF is time consuming and expensive. And they have gone to Stainless Steel transport tanks rather than aluminum, something about the corrosive effects DEF has on aluminum probably why all the class 8 trucks I've seen have a plastic tank with a shiny cover. Exposure to sunlight is another thing that effects DEF's longevity in storage.

 

[CAROLINA CUMMINS]

My employer runs 700+ Class 8 trucks (95% Freightliner w/DD15's) and while we have a lot of aftertreatment issues, a very small percentage is the actual DEF. And that is usually caused by a driver - adding washer fluid/coolant/diesel fuel/additives etc...

 

[gsbrockman]

probably why all the class 8 trucks I've seen have a plastic tank with a shiny cover.

No......they have plastic tanks to allow for the inherent expansion and contraction of DEF since it freezes at 12*F......

 

[slowmover]

A sealed jug that got too hot during transport or storage concerns me more than an open underground tank with a very constant storage temp.

I’m willing to bet that turnover is pretty high at truck stops with pumps. Many OTR trucks use SCR, and I don’t see them using the jugs to fill their much larger tanks.

It would be interesting to see the sales numbers between jug and pump thou.

I hauled DEF for awhile. Major truckstops go through 3-4,000 gals per week. (Some even more).

In the 2019 Peterbilt 579 I’m driving (13L Paccar, love it with 12-speed automated manual), I do what I’ve been doing for years: always fill DEF tank when getting fuel. Mine holds 19-gals (truck holds 220 of diesel), so a typical fill is maybe 140-gals diesel and 5-6 gals of DEF.

I’ve never had DEF problems.

IDLING is probably where guys get in trouble with re-gens and the rest. Just don’t. DEF is last chance to clean things up so avoid situations that call for a lot of that liquid fertilizer.

And too much engine. Fleets are learning they have emissions problems with wrong engine spec. Too big = problems.

For a pickup it’s having bought one of these with no use for it. Empty truck = Stupid. It’s trying to stay compliant while being used outside of specification.

Only pickup I ever saw with DEF problem was a Maxipad sat six months in South Texas. 2013 or so. Owner had a huge bill.

“Well, I had to get A DIESEL for my camper”. Ha! Shoulda bought a better camper. Big & Stupid describes the fifth wheels they sell in this country. Can’t even see out of them.

I saw the US, most of Canada and Mexico before college. Five of us in a car and a 28’ Silver Streak out back (that’s still on the road 44-yers later). . Wouldn’t change a thing today. You don’t need a pickup 9 times out of 10 if the trailer is right. As it’s a crap tow vehicle for what matters.

Any pickup is a business vehicle, or it’s little boy ego. Wrong vehicle spec without IRS depreciation and/or deductions.

Otherwise:

DEF in UNDERGROUND STORAGE at a NATIONAL chain Truck & Travel Center is always your best bet. Keep tank filled.

(You have a T/A in Boise. Use it. Get a corporate fuel card.)

Your local jobber probably has poly tanks in a building. Fills his little tanker to service farm/ranch. Harvest season is busy as hell. I’ve had to refill them from my big tanker out in a field. Employees aren’t good about cleanliness. So it’s not where I’d fill mine.

.

 

[WalterJ]

Really can’t compare the SCR systems that are in “Consumer grade” class 4-5 rigs with class 8 SCR systems. For starters, the class 8 DEF pumps I see have serviceable filters, Urea quality sensors (to spot bad DEF right away, and not by NOx readback when it’s too late) and engine coolant tank heater systems to better prevent ice ups.

Greetings; I just committed to purchase a new 2018 2500 diesel & recalled all the problems my son experienced with his 2013 rig. Has FCA resolved those DEF related 'quality" issues or sensors? Thanks...

 

[Wiredawg]

Greetings; I just committed to purchase a new 2018 2500 diesel & recalled all the problems my son experienced with his 2013 rig. Has FCA resolved those DEF related 'quality" issues or sensors? Thanks...

I have a 2017 Ram 5500 I haven't had any DEF problems and not seeing to many reports either.

Just buy good DEF, don't put DEF in your fuel tank, and keep DEF tank full. Figure out where the DEF gauge shows what equals either a gallon or 2.5 gallons down and refill.

Anyway, just like anything else on the TDR, you'll get different opinions, so there is mine.

Good luck, Ron

 

[Larry Willard]

I have a '13 truck and never had any DEF related problems, although I have only driven a little over 80000 miles.

 

[WalterJ]

All DEF from Factory is exactly the same because the Spec is perfectly tight.
There is simply no better or worse DEF available.

Greetings on this old thread;
I did not see where the 2018 manual states what source of DEF is required. I mean, my son's 2013 had issues, some mechanics attributed to using Non-Mopar DEF fluid. Sounded goofy to me, but I wasn't driving a DEF truck, now I am. Care to comment, again? Thanks.