Does my usage warrant diesel? Cummins 6.7 with AISIN...

[Danattherock]

First of all, having read many, many, old threads here. I want to say up front, the initial cost of the diesel, gas mileage, and ongoing cost of regular oil changes and maintenance are not considerations with my decision. My only concern is which motor will be most reliable in the years to come.

Wife and I have decided on Dodge 3500 Mega cab Laramie SRW 4x4. Hauling 27-28' Airstream (7-8k lbs) through Smoky Mountains of NC and Tenn a weekend or two each month and a big 2-3 week trip each summer out west is main towing usage.

My concern, my daily driving is just 5-7 miles (45-55 mph) into and from town, once weekly driving 30 miles away and back seeing family. And once a month 2.5 hours away to the coast to see family. Sometimes more highway driving, but this is the minimum average.

Then soon adding an Airstream, which we plan to do soon after buying TV. We will take at least one weekend trip a month to the Smoky Mountains of NC and Tenn which is 4-5 hours one way.

Is that enough to keep a diesel happy?

Read they need to be driven a lot to 'clean out'. Read various ramblings about 'Regen', throwing 'Error codes', and such, but not sure how much driving style plays into this. My concern is my driving style may better suit the gas 6.4 Hemi.

An additional variable, I'm very interested in the AISIN $2400 transmission upgrade, but it's only available in the Ram 3500 with Cummins 6.7 diesel. So if going with gas, I don't have this option available to me. Anyone familiar with AISIN? Would love to hear about it.

Our primary goal is to have a long trouble free engine life. Plan is to keep truck a long time. We don't buy new cars often. We take care of them and keep them around. My main question is for our intended usage, do you think the Cummins or Hemi 6.4 would be best?

Thanks for any insights you may share.


Dan
NC

[Tystevens]

Dan, you want the diesel ... get the diesel! IdaD's post is on point. Really just comes down to what will put a bigger smile on your face when you're using it.

Good luck!

[jerem0621]

Dan,

Your minivan comment made me chuckle from memory of our Minivan Purchase...

We were seriously looking at buying an Excursion...went to look at some and ended up with the Minivan. I am very pleased with it pulling our 2,900 lb PUP over Monteagle (at 55-60 mph at 2,800-3,500 RPM's)

My pup has a King Bed, queen bed, oversized couch that makes a big single bed, and an oversized slide out dinette that makes a large full size bed. Wet Bathroom, shower, AC, Heater, fridge, outside grill and 15-17 mph pulling. Lol

My dream TT is an Airstream as well...I want a 1982-1988 34 Ft triple axel Airstream. They were a little lighter back in the 80's...before they went to the wide body design.

But, split bath, rear bedroom, dinette, couch, curb weight is about 5500 lbs on an 82 with a GVWR of 8300 lbs.

Should be a fun project.

Thanks!

Jeremiah

[Danattherock]

Thanks Ida.

I have complete confidence the Hemi 6.4 would be plenty to haul the 6-7k lb Airstream I intend to buy. I also think it being lighter and HP being applied differently would be a bit more nimble off road with my other interest, shooting and fishing primarily.

But can't get past the low reving diesel trip up the mountain, and jake brake controlling the decent. Smoky Mountians of NC are mainly where we will use our camper. I've perhaps not given enough consideration to my intended usage. I've read it a thousand times, if mountains, go diesel.

Adding fuel (diesel and gas) hah, to the Fire, I think I read a lot of BS regarding diesels failing and such early on. Went back and revisited a few forums and threads. It does appear to be the younger kids deleting, tuning, and hopping up trucks that atleast in part led to the issues I heard about diesels.

A few more experienced, yes older, but much smarter, guys here and on Airfirums (Airstream forum) were nice enough to reply or send PM's that opened my mind to diesels once again. I'm not normally bat shet crazy. I can see why diesel vs gas is the eternal web debate.

With today's motors, I'm sure I will be happy either way. Will likely end up with a mini van!! Haha. Thanks for all the patience and insights here. Both are highly valued.


Dan

[IdaD]

I thought you already decided to go with the Hemi? If you haven't done it yet, you really ought to go drive both and just see what you think of them - they really do drive a lot differently. The Hemi can handle your load and the CTD can handle a short commute, so it really comes down the preference. The money component is a wash in terms of the overall cost of ownership.

I plan on owning my truck 15 years, so you can see where I placed my bet on longevity.

[Danattherock]

Thanks for demystifying the regen.

Makes me wonder what wing nut typed some earlier stuff I read.

Appreciate your time and thoughts.


Dan

[blofgren]

I think what Cummins12v is saying is that EGR function and regenerations are significantly reduced with the introduction of DEF to the Cummins in 2013. I am going on 16k kms (10k miles) in mine and I only noticed 1 regen last winter when I wasn't towing and using the truck for more short trips than I normally would. The only way I could tell is that the fuel economy went down and I noticed the exhaust cooling off (ticking) much more when I parked it in my garage. The truck did not perform or run any differently than normal and I would hazard a guess that most people don't even notice when they are in regen.

I can tell you that my truck has virtually no smell when I start it in my garage, much less so than my wife's gas Acura MDX. The new diesels run so clean it is amazing.

My 2 cents worth to you; given that you are looking to keep your truck for a very long time (such as me) I think buying the Cummins over the Hemi is a no brainer. You will enjoy much better towing performance and better fuel economy both solo and towing. The new SRW Cummins are presenting some pretty impressive fuel economy figures. The truck will also be much more desirable at resale time and will fetch you a lot more $ than the gas truck will, which offsets much of the initial cost. Again, just my opinion!

Given, I tow much heavier than you but the Cummins pulls so effortlessly it is really hard to describe until you have experienced it! I usually also prefer to take the truck over the SUV almost everywhere, even short trips, because it is so much fun to drive. Don't forget about the added bonus of the exhaust brake which also works amazingly well. I used to feel a bit nervous about towing in the mountains because of descending mountain grades, and it no longer bothers me in the least now and am towing much heavier than I was with my past trucks. Needless to say I am a happy camper! :B

[Danattherock]

Why?

Eager to hear.

Thanks for those last few replies. I'm on fence so bad sac is sore.



Dan

[Cummins12V98]

The 13 and newer Cummins are not so sensitive to the short trips.

[noteven]

Ok I'll join in the silly game:

Why would a modern light duty diesel engine be bothered by cold starts / short runs any more than a modern spark ignited gasohol engine?

Are they made out of different materials or something?

A short drive empty truck light duty diesel should be using so little fuel it shouldn't be bothering it's after treatment too bad.

Abrupt throttle increases rather than letting the engine build manifold pressure = "smoke" so if you are always romping on the throttle "rolling coal" (if you didn't have a coal filter) you will load up the DPF with coal and it will need to regenerate sooner rather than later.

[goducks10]

So what about the guy that's full timing. Parks his 5er at one spot for 1-2 months. Then spends 1-2 months putting around town in his diesel truck going here or there for what ever reason. Then hitches up and drives 300 miles and repeats the same scenario. Not much different than some of us that do short hops all month and then takes it out for a tow.

[Tystevens]

Danattherock wrote:
My concern is how a diesel motor will hold up 10-15 years down the road being used as a daily driver, short 5-10 mile daily commutes, and such. Read over and over they need to be driven hard, long hwy miles, get to temp, etc to keep the EPA mandated junk under the truck working and avoid soot clogging (expensive) repairs. I'm buying a truck to keep 10-15 years. I'm interested in what truck will be most reliable and trouble free for the long haul. What I've gathered, that is the 6.4 Hemi gasser. Any contradicting opinions welcome.

I have not been following the diesels very closely for the last couple years. But a lot of the 'internet knowledge' you'll find on diesels (and all engines, really) tends to mash together concepts pertaining to older diesels, newer diesels, and everything in between, with a good dose of shade tree mechanic guesstimation and internet lore mixed in for good measure. So you have to take it all with a grain of salt -- diesels have changed a lot over the years. Some have good, real world experience; others think their old 12V Cummins is the same as a new 6.7 just because it has the C on the valve cover.

If there is a diesel you want, I'd spend some time over at a brand-specific forum, see what kind of problems are popping up and what does not seem to be an issue.

Personally, I don't think I'd have any concern buying a diesel for the use you've proposed (take that with a grain of salt, too!).

[gtsum]

I dunno about longevity and short rides, but mine is my daily driver also..some days I might drive it 10 miles, some days I might drive it 100 miles...and we camp about every other weekend so between all the above, I am putting a load on it fairly regularly. I cannot see how a gas engine will outlast a diesel, but I am a diesel newbie (31k miles), so who knows? I just know it pulls better and the exhaust brake on the cummins works great.

[Danattherock]

Thanks man. That sounds like a sweet truck. I'm certain it pulls well.

My concern is how a diesel motor will hold up 10-15 years down the road being used as a daily driver, short 5-10 mile daily commutes, and such. Read over and over they need to be driven hard, long hwy miles, get to temp, etc to keep the EPA mandated junk under the truck working and avoid soot clogging (expensive) repairs. I'm buying a truck to keep 10-15 years. I'm interested in what truck will be most reliable and trouble free for the long haul. What I've gathered, that is the 6.4 Hemi gasser. Any contradicting opinions welcome.


Dan

[gtsum]

if cost isnt an object, then no question get the cummins. They simply pull better and more effortlessly. I pull 16klbs in the mountains and it works well. I have the 68 tranny and it works fine, but 16klbs in mountains can use 3.73 gears..which cannot be had on a SRW...even though I ordered my truck last year I am ordering a 2016 dually with aisin for my weight and driving locations.

For your weight a SRW would be fine, but if you ever consider going bigger in the future keep in mind a DRW opens up more doors.

As an aside, I can get about 300 miles per tank towing (10mpg towing the 16k)...towing quads on flat trailers in the mountains I can get about 16.5...buddies with gassers and same weight and same trip get about 9...that equates to quite a bit more stops. Good luck!