Define "short trips" please (Cummins question)

[Michael Phipps]

OK, so I've ordered a new PowerWagon and I'm happy with that decision, but I came THIS close to ordering a Limited with the Cummins. The number one reason I didn't go that route is confusion on this point- What exactly is a short trip?

For example, nowadays 90% of my driving is back and forth over the same 17 miles to work. Its all highway, but with rush hour traffic it's alot of stop and go. Not much cruising. I'll actually get on the highway and drive > 1 hour about once or twice a month. My >3 hour trips are about once every six months. I also don't tow/haul very often, but when I do I'm towing a car on a trailer. If I were to buy a diesel, it would simply be a preference rather an overwhelming need to have a workhorse.

So, is what I'm doing "short trips"? If not, what is a short trip? I'd hate to buy a brand spanking new diesel and then ruin it because I didn't drive it enough. I had an '81 Trans Am like that when I was a kid. If I didn't drive it hard at least once a week it just straight up wouldn't start on me like it was punishing me for not having fun...

 

[JayLeonard]

I have a 2021. I do a lot of short trips of 1/2 mile several times each week. Its my daily driver. But I do haul our 30 ft travel trailer for 4 months in the summer ( from Florida), so it gets to work at times. Of my 56 k miles, I am going to guess 40% is towing.
I cant see a 17 mile daily commute hurting anything. But being from Florida I never see cold and how that may affect things.
Im interested in other opinions.

 

[crash68]

So, is what I'm doing "short trips"? If not, what is a short trip?

A "short trip" for a modern diesel is one where the engine (coolant and oil) doesn't get up to full operating temperature and/or the emissions system isn't capable of completing a regeneration cycle. Your 17 miles daily might not be long enough for a regen to complete(depending on the ambient temperatures), there is both temperature and rpm requirements for a regen cycle. Usually if a diesel is ran at freeway speeds for a good half an hour weekly that should keep emissions, if not you'll get a notification on the dash to keep driving the vehicle.

 

[Michael Phipps]

Good to know! I've never had anyone define the short trips for me, just that they were bad.

 

[NewBlackDak]

I would call a short trip anything that doesn't get up to full operating temperature. I usually have a trailer on a couple times per week, but I make sure to stretch it's legs at highway speeds on the rare weeks I don't.

 

[Dean2]

There is a gear limiter in these pickups for a reason. If you tend to drive shorter trips, limit the max gear so you get the RPM at higher levels and operating temperatures up to full heat. When most diesels were manual, you shifted at x RPM, which was top of the torque curve, and drove steady state at Y RPM, which was usually middle of the torque band. I drive my gas vehicles the same way, and interestingly enough, fuel mileage, as well as lots of other stuff, benefits from the extra RPM.

Not a complete solution but a diesel hates to be lugged, the heavily emission controlled ones even more so, and the auto transmissions are designed to keep revs low.

 

[crash68]

Good to know! I've never had anyone define the short trips for me, just that they were bad.

You can't really put a number to " short trips":as that sorta changes based on ambient temperatures and how the vehicle is being driven. Diesels will cool off when just idling or at low speeds and they typically hold multiple gallons of oil which take longer to get warm in colder climates.
The only sticking point is if the emissions system can get up to temp and have enough time to clean the DPF, a good half hour at highway speeds once a week should keep things good.

 

[Burla]

Use cetane boost from day one all the time.

So 17 miles is right on the line, what you need is the exhaust to heat up the metals get to a certain temp, not operating temps. Even if you are at passive Regen at that point, it wouldn't be for long at that mileage.

 

[crash68]

There is a gear limiter in these pickups for a reason. If you tend to dreve shorter trips, limit the max gear so you get the RPM at higher levels and operating temperatures up to full heat.

Not so much needed to use the gear limiter as the engine management will utilize the turbo vanes and even hold transmission gears to help in aid warming the engine.

 

[06 Dodge]

OK, so I've ordered a new PowerWagon and I'm happy with that decision, but I came THIS close to ordering a Limited with the Cummins. The number one reason I didn't go that route is confusion on this point- What exactly is a short trip?

For example, nowadays 90% of my driving is back and forth over the same 17 miles to work. Its all highway, but with rush hour traffic it's alot of stop and go. Not much cruising. I'll actually get on the highway and drive > 1 hour about once or twice a month. My >3 hour trips are about once every six months. I also don't tow/haul very often, but when I do I'm towing a car on a trailer. If I were to buy a diesel, it would simply be a preference rather an overwhelming need to have a workhorse.

So, is what I'm doing "short trips"? If not, what is a short trip? I'd hate to buy a brand spanking new diesel and then ruin it because I didn't drive it enough. I had an '81 Trans Am like that when I was a kid. If I didn't drive it hard at least once a week it just straight up wouldn't start on me like it was punishing me for not having fun...

JMHO, A short trip is classified as any trip that is not at least 10 miles one way at speeds at or over 40 MPH or where oil & water do not get up to full operating temps aka late fall to early spring time depending on your location... A real killer of DPF is very short 1-3 mile trip, now if your driving 9 miles one way, 18 round trip and you do get a diesel you will need to get it out on the hwy at least every week for a good 30 mile non stop drive at hwy speeds of 45 mph or greater, I would use a good Cetane booster along with not using diesel fuel that contains more than 5% bio unless its state mandated like MN, KS an a few others..

 

[18CrewDually]

I didn't see anyone else mention it but the deal breaker is not only the 17 mile trips, but the slow stop & go rush hour traffic you sit it while commuting with no cruising. That's not really "highway " driving.
To me, your best bet is a gasser.

 

[Rebel4Mo]

This is why I bought a gasser.
The commute to my work is 8 miles and I dont tow very often.

 

[BossHogg]

It is much easier to get the engine to operating temperature in the summer than it is in the winter, so this point varies the definition of a "short trip" in the context of a regen.

I've noticed, on my 2015 Cummins, using a Bank's iDash, once the engine has reached operating temperature, the regen cycle will start. My MPG will drop down to 18 MPG and then slowly increase over the next 12 to 15 minutes back to the normal number of 24 MPG. I typically drive on roads with speeds of 45 to 55 MPH in a rural setting.

I've also noticed my 2022 ECODiesel behaves much the same, albeit it takes longer to get to operating temperature. In the winter, it is tough to find an operating temperature even on medium-range drives.

 

[Michael Phipps]

So I did end up going gas- 6.4l Power Wagon- and I'm convinced now more than ever it was the right call. As much as I love the sound of a diesel, and appreciate the pure stump pulling power of one, I'm convinced my use case would have caused more problems than it solved especially in the long run. Thank you all for your advice!

 

[Dean2]

So I did end up going gas- 6.4l Power Wagon- and I'm convinced now more than ever it was the right call. As much as I love the sound of a diesel, and appreciate the pure stump pulling power of one, I'm convinced my use case would have caused more problems than it solved especially in the long run. Thank you all for your advice!

Good choice, very sure you will be a lot happier with the gas. I too really like diesels but they don't make sense if you aren't doing a lot of towing, and even less as a daily, short trip driver. It is why I run a 2500 long box with the 6.4 now. For the few times I need to tow something it has lots of power, and it does everything else so much better.

 

[Burla]

So I did end up going gas- 6.4l Power Wagon- and I'm convinced now more than ever it was the right call. As much as I love the sound of a diesel, and appreciate the pure stump pulling power of one, I'm convinced my use case would have caused more problems than it solved especially in the long run. Thank you all for your advice!

good on you, very smart.

 

[Frisk]

Not directly related but I used to have a 2004 VW Jetta TDI. On long trips on the hwy I would easily get 60 mpg and even in city driving during long trips I would be getting in the 50s . My work location changed and my daily drive was about 8 miles.....Mileage went down to sub 40 mpg. The car would still get great fuel mileage on long triips but the short daily trips were not its thing. I would not get a new diesel vehicle unless I was driving it longer distances and needed the towing power. The short trips will give you lots of grief with the emmissions systems too. I do miss the plain fun of driving a small car with instant torque....No need to downshift to pass.

 

[Neomoritate]

Your Short Trips are creating soot. That soot gets trapped by the Diesel Particulate Filter. The trapped soot needs to be burned out in a ReGen Cycle. ReGen Cycle happens in about 20 minutes (after Exhaust Gas gets up to full temp) of Full Speed highway driving, which you can effect faster if you use the Gear Limiter to increase RPM.
I drive a 2018 1500 Ecodiesel, 130,000 miles, all Stock equipment. Mostly city stop-and-go. A drive to the suburbs every week or two keeps the MIL off.

 

[NotSoFast]

I live at 7000 feet, and the diesel is wonderful for towing, with no altitude decrease in power. But one winter when it went a few months without getting good and hot, I started getting DPF issues. Good and hot is way hotter than getting the water and oil hot: the exhaust system needs to get hot enough for long enough to burn out the soot that accumulates when the truck is getting warmed up. The soot is probably not really being generated all that much once the engine is up to operating temperature, but that doesn't get the exhaust system hot. I have heard that the 2025 turbodiesel has a DPF heater, so it might get hot quicker. (Does anyone know?)

Diesels are more efficient, so they take longer to get warm. (And they have more mass.) In winter, I think any trip with stop and go driving would count as a short trip unless it involved towing a heavy load up a sharp grade. The gear limiter is especially good during a regen cycle.