Why Are Short Trips Bad for the EcoDiesel?

[VonSquid]

There are numerous references throughout this forum that the EcoDiesel will "die" if subjected to short (around town) type of trips, as opposed to long-distance driving. Wondering if anyone has the "science" behind this claim?

 

[Sascwatch]

The main issues I can see with short trips in a modern diesel has to do with the emissions related components. The dpf needs to be cleaned out from time to time which requires highway driving, I’ve read that during a regen cycle excess amounts of fuel can enter the crankcase and will take some time/temps to evaporate and burn it all. Other than that I’m not sure what it would hurt.

 

[Rossum]

Yup. Ever see all the black soot most any older (non-DPF) diesel makes when it's started cold? That still happens and it all ends up trapped in the DPF now. Short trips won't burn it off. To make matters worse, even the active regens that the ECU will use to try to fix the problem may not complete during short trips. In addition diesel engines take longer to warm up the coolant and oil than gassers. If you know you're going to do primarily short trips, get a gasser. Of if you insist on using a diesel this way, take it out on the highway and drive it like you stole it for an hour once a week.

 

[bill-e]

I think if you live in the country/rural it doesn't matter much. While we don't have highways we often have to drive some distance to go the a store or restaurant which get's the truck up to temp. In my 5 years of Gen 2 ownership I only got the 80% regen warning on the EVIC once. I had an Edge CTS2 installed so I was constantly aware of what was going on with soot levels. As long as you can get your truck up close to operating temp the computer will try to regen. Every minute of regen reduces the soot load so even if you don't totally clean it out, or even hardly clean it at all, you have reduced the soot load and the truck wont try to regen again until it get's to its trigger points which on the Gen 2 was between 65 and 70%+/- and 80%. The reason most of us never see the EVIC message is that because of the passive and active regens, the truck seldom gets to that 80% point.

Now for more unscientific info gathered over the last month and a half, utilizing time between active regens as a indicator of the amount of soot the EGR is putting in the engine, my Gen 3 is producing at least 75% less soot through the engine.

So given my experience, I personally would tell someone who asked me the OP's question to go ahead and buy the EcoD if that's what he wants.

 

[RunsWithBeer]

IMO DPF is an abomination to the engine. I stopped buying diesel engine vehicles when that became the norm. Even in the early 2000's when manufacturers were struggling to get EGR to work properly, many people were having to bypass the EGR to keep their engines running properly.

I remember when a friend bought a new (at the time) Cummins powered Dodge with the first DPF. He was in and out of the shop multiple times trying to get it working properly.

Admittedly, those older engines did help reduce tailgating, if you lifted your foot and stomped it back down, it tended to encourage proper following distance from those behind you.

 

[Aseras]

The main issues I can see with short trips in a modern diesel has to do with the emissions related components. The dpf needs to be cleaned out from time to time which requires highway driving, I’ve read that during a regen cycle excess amounts of fuel can enter the crankcase and will take some time/temps to evaporate and burn it all. Other than that I’m not sure what it would hurt.

This is diesel in general. It is a fuel oil. Ever notice how the pumps are always grimy and dark? It does not evaporate. The main reason you need to change the oil in a diesel is fuel dilution of the oil. Also since ULSD ( ultra low sulfur diesel ) was mandated the lubricity SUCKS and is barely adequate. Now you have your lubricating oil diluted with a non lubricating oil. So you either suffer more wear or the level goes up enough to cause a diesel engine to go into a run away if the oil rises to the crank and get beaten into a foam and get burped up the intake.
Short trips do not let the diesel engine get warmed up well enough to remove deposits and keep carbon from accumulating and being burnt off. That's all really. You need at least 15-20 minutes of loaded running to get it to temp and say about 1 hour straight a month of highway driving minimum to keep it all happy. diesel engines are made to be used and worked. idling won't cut it.

 

[Aseras]

IMO DPF is an abomination to the engine. I stopped buying diesel engine vehicles when that became the norm. Even in the early 2000's when manufacturers were struggling to get EGR to work properly, many people were having to bypass the EGR to keep their engines running properly.

I remember when a friend bought a new (at the time) Cummins powered Dodge with the first DPF. He was in and out of the shop multiple times trying to get it working properly.

Admittedly, those older engines did help reduce tailgating, if you lifted your foot and stomped it back down, it tended to encourage proper following distance from those behind you.

DPF are good. So are catalytic convertors. You can be behind a modern diesel and not have a black cloud of "coal" come out. The crap implementation on passenger vehicles is the problem. They should be easily replaceable cartridges like on commercial engines and less restrictive.

 

[WXman]

For the record, the soot doesn't "burn off" unless temperatures are 650F or higher inside the DPF. This doesn't happen on my truck unless I'm towing or I'm at 70 MPH on the interstate. I'd be willing to bet that a large percentage of EcoDiesel owners' mileage meets neither of those scenarios. So the idea that short trips will kill the engine is unfounded, in my opinion. Stop and go in the city or 55 MPH on the highway with the cruise control set are both going to require active regen cycles, and on this new Gen 3 engine the regen cycles are so fast and efficient that you can't even tell they happened.

 

[J-Cooz]

I've watched my fuel economy on the highway to try and see if I can tell when it's doing a Regen and I've never been able to see a noticeable drop. I do almost exclusively highway driving on long trips so I'm sure my regens are few and far between.

 

[Sascwatch]

I swear I can smell the heat from my truck after it does a regen and I park it, the exhaust also makes a lot of noise cooling down afterwords like most stainless steel exhausts do.

I am now at just over 22000 km on my truck and have only gotten the “dpf filter is nearly full, drive at highway speeds for regen” message once during covid shut downs where I didn’t leave town for a week. It took about 7-8 minutes on the highway at 55mph to clear it up.

 

[Rossum]

55 MPH on the highway

Why does a certain Sammy Hagar song come to mind here?

 

[Aseras]

I swear I can smell the heat from my truck after it does a regen and I park it, the exhaust also makes a lot of noise cooling down afterwords like most stainless steel exhausts do.

I am now at just over 22000 km on my truck and have only gotten the “dpf filter is nearly full, drive at highway speeds for regen” message once during covid shut downs where I didn’t leave town for a week. It took about 7-8 minutes on the highway at 55mph to clear it up.

If you drive like WXMan said it will not get hot enough to do passive regen and then it triggers an active regen when the soot is built up. it will inject diesel on the exhaust stroke and into the dpf directly to raise the dpf to cook off the soot. It gets very hot and you can definitely smell it. Part of that is also that it is injecting a ton of DEF/Urea to catalyze the NOx and you smell the excess of it too.

 

[StuartV]

IMO DPF is an abomination to the engine. I stopped buying diesel engine vehicles when that became the norm. Even in the early 2000's when manufacturers were struggling to get EGR to work properly, many people were having to bypass the EGR to keep their engines running properly.

I felt the same way when DPF first started showing up on pickup trucks.

Nobody should be surprised that the first few years of it had issues. That doesn't mean that newer trucks still have those teething issues.

Now, I am totally in favor of DPF - because I came to this realization: Without DPF, the manufacturers can only tune the engine so "hot" before they hit EPA emissions limits. With DPF, they can tune the engine to run better, make more power, and get better fuel economy - because the exhaust gas coming out of the combustion chamber doesn't have to be AS clean - it can be dirty and get cleaned up by the DPF/exhaust system.

It's 2020, I think the manufacturers mostly have EGR and DPF figured out now.... Not to say nobody ever has a problem with it now. Just, that it's nothing like it was in the early 2000s.

 

[Rossum]

Now, I am totally in favor of DPF

Remember when we first got catalytic converters on gasoline engines in the mid 1970s? They were a total PITA. But prior to catalytic converters, there were V8s making barely 150 HP. Manufacturers eventually figured out how to make catalytic converters work reliably with fuel injection and heated oxygen sensors, and now we have V8s of the same size making 350+ HP.

Diesels have also come a long way. I mean look at what we have today: 3.0L 6-cylinder diesels making 250+ HP and 450+ ft-lbs of torque, yielding nearly 30 MPG in a full-size pickup truck. That's performance and efficiency that would have been inconceivable 20 years ago.

 

[NewLove]

Also, guys say it has to be “Worked”... but I have a hard time figuring out what that actually means?..


Sent from my iPhone using Tapatalk

 

[bill-e]

I think all it needs is to have enough regen opportunities so that you don't ever have to bring it to the dealer for a parked regen. If you have short trips you'll need more opportunities but in the last 5 years I haven't seen much in the way of people claiming that they got to 100% DPF full.,,,it's a non-issue

 

[NewLove]

I’m surprised it doesn’t tell you when it’s in regen.. I think it should.


Sent from my iPhone using Tapatalk

 

[bill-e]

I’m surprised it doesn’t tell you when it’s in regen.. I think it should.


Sent from my iPhone using Tapatalk

It will tell you for the 80% regen which most people never even reach because the passive and active regens prevent that from happening but once in a blue moon.

 

[Dragonmaster13]

Considering 90% of vehicles sold in Europe (where this motor comes from) are diesel and their emissions are required to be slightly lower or the same as US/Cali, and they are still driving diesel and most Europeans only drive in the City, I don't think there's an issue like there was on the early 2000's (10-15 years ago!) motors. Have you heard of more than a handful of people having clogged EGR/DPF on the Gen 2 Ecodiesel? I don't think so. With the Gen 3 "Improvements" likely even less of an issue. Buy what you want and need and forget about it.

 

[Aseras]

Except the old truck will throw a warning light and keep going. These new ones will brick themselves and even the dealers cant fix them.