Does anyone else have a truck like this?

I guess that was what kinda set me off, I'm long over it, no sweat on my end. I agree that the engine manufactures were sold a tough bill of goods and a short time to do it, but I guess that is my point.

They, as a group, had/have so much more pull as large companies than we do as individual owners, I truly believe if they would have pushed back a bit the situation with these newer motors would be different.

As an aside, I do think things will improve, and although it is comparing apples to oranges one has to look back no further than 1971, when emissions first started tightening in cars, look at what happened.

You had muscle cars that were putting out almost 500hp in 1970, fast forward to 1976 when even the Corvette could only muster a pathetic 250hp, then look at what happened.

Because of increased competition from other countries, and improvements in technology you can right now go down to a GM dealer and buy a station wagon, that's right a station wagon with 556hp right off the showroom floor.


Guess what, it idles nice and smooth, it has no hiccups in it's power band, it runs gas that cars of 70's would puke on, and on top of all of this, that station wagon will get almost 30 mpg on the highway.

BTW, the new Corvettes and Viper, along with some other "emissions" supercars are OVER 700 HP!!! Performance and emissions IS possible, maybe not easy, but possible.

Of course there is a difference between a gas motor and a diesel, but they are BOTH ICE derived power plants, in fact, the gas motors of today, with high pressure fuel injection and turbo's and higher compression ratio's are much closer to a diesel than at any time in their past.

The technology is out there, we as consumers just got the short end of the stick!

 

Yes but isnt it easier to build a 600hp motor without all the emissions crap. My deal is diesels are cleaner than gassers yet they slap more emissions crap on diesels. I read up on your last comment with the truck setup thats crazy if everything is the same. Im surprised that cummins pulls that well with that short of gears. Then again.your grossing a lot less than i am. I rarely see a scale ticket under 79k gross. And of course areodynamics means nothing to a shipper

 

Believe me 379, this has my freightliner/detroit rep, shaking his head, he has seen first hand the calculated miles and fuel consumption of both trucks on identical trips.

I am NOT saying that MN Driver is wrong about bumping up the HP/TQ, the ONLY reason we haven't done it was I was trying to get one of the trucks out of warranty before we did it.

I also completely understand what he is saying about running that motor at it's top output, but just for arguments sake let's look at the two motors,

The DD13 as stated is available in ranges from 350/1200 to 470/1650 we are two power levels from the top, AND my freightliner rep, says that he doesn't think he can get us to 470/1650 and still stay in warranty, has something to do with this being a S/A I believe. So 450/1550 is probably it for us.

Now, the ISM can go from 285/1150 to 500/1550 my Pete is at 425/1550 yes I do have 15hp and 100 ftlbs/tq more than the DD13, but I am NOT at the top of the power rating for this motor.

But the ISM consistently is in or close to the magic 9mpg, we just finished the IFTA report for all of the DD13's for last quarter, those engine as reported on Ifta for a whole quarter are at 7.26

I'm sorry, but to me this is a huge difference, and when you add in that the smaller motor out pulls the bigger one, it just doesn't add up.

 

You can see from this rating file what our curve is, our trucks at 70mph are running right at 1500rpm, as you can see, we are FAR from the bottom of this engines sweet spot.

I was always told that you want your engine to be running at or just above peak tq, rpm, so that when you encounter a pull you are pulling down "into your tq curve, which as you can see, is exactly what we are doing.

This tq curve IS FLAT all the way from 1400 to 1000 rpm.






View attachment 1.13-DD13-Spec-Sheet-FNL2-DDC-6213.pdf

 

I definitely understand what you're saying with the warranty stuff. MN Driver does know his detroits very well won't take anything away from him when it comes to detroit engines, however I also understand where you're coming from compairing that smaller cummins to the larger detroit in power and fuel milage.

I don't know a whole lot about the smaller motors when it comes to pulling the lighter loads. As I said I don't run light I'm heavy 99.9% of the time however I do know that with more power and a larger motor least between the 2 trucks I run my truck 600 horse 15.8 will get better mileage than the 15.2l acert at 550 horse. There's roughly 1 mpg difference in the 2 trucks although they're pretty much identical. And I also know what you're saying about that cummins getting more fuel economy when you're picking up 1.5 mpg roughly on less power and a smaller motor that says a lot.

Honestly my best recommendation for you (if you can afford it) would be to slowly phase out the detroits if the uprating doesn't help you out after the warranties run out. Not trying to tell you how to run things but that would be my suggestion if you can get trucks specd like the pete with the cummins that you have, even paying a little more you'll make up for it in the fuel savings alone in a matter of a year. As you probably already know haha.

By all means I like giving everything a chance but if it don't work and it's more economical do to go a different route by all means do it. Good luck with everything hope it works out for you in the long run.

 

Thanks, appreciate the insight, and I wasn't saying that MN isn't familiar with Detroits, I'm sure that 12.7 has served him well it WAS a good engine, at one time we had several. BUT, this DD13 is a COMPLETELY DIFFERENT animal than what he is running.

To be honest, I don't even know if his S60 is an emissions motor with EGR, or not, and they never made a 12.7 with DPF as they were all turned into 14.0 by then, maybe he will chime in and let us know.

 

Hi KT. I noticed you said that you've had to replace dpf canisters on the Detroits already... and sensors... now I'm running the last s60 Detroit made before phasing out the 60's and replacing them with the DD series, and the one sensor I have had consistent problems with is the turbo boost pressure sensor in the intake manifold. It gets plugged with soot and performance falls off, it happens gradually until it gets to a point where the turbo boost is wildly fluctuating, at that point it's failed completely. Detroit calls this phenomena, the gradual loss, "failed within spec".... I'm wondering what's happening with yours, what's causing the dpf's to plug prematurely? That may be where the answer lies, finding out what's causing these motors to plug the dpf's up... How often do you have to run a manual regen on these units, if ever?

 

Hey Trees, we have been replacing the DPF's right at 300,000 so far have replaced three, dealer says that 300,000 replacement is normal?
Cost about 1800.00 to replace one.

As far as the sensors go, we have had a couple of different issue, not just any one that sticks out. We have also replaced 2 full sets of injectors and one half set, and I think I have another one starting to act up.

I really don't have much of an answer for your sensor issue, other than I was told that the S60's basically had emissions controls "hung" on it" and the DD13/DD15 was/is a ground up design with the emissions being an intricate part of the motor, so maybe they have "eliminated" that issue?

Manual regen just depends, some trucks never have, others maybe once every two months. We have had several EGR valves either replaced or cleaned.

 

The other problem that I had that caused a lot of troubleshooting problems was the temp sensor on the turbo housing, the wire had nicked and there was a really small amount of corrosion, this corrosion caused additional resistance within the wire, which changed the value slightly, which caused the ecm to alter all of the other systems, to change their values to compensate.... it would manifest itself as a "high dpf outlet temp" and would throw shut down codes, I had techs telling me everything from, "you have a bad fuel injector that's overfueling", to "you have a bad temp sensor in the dpf"... UOA's never indicated fuel in the oil, so I ruled out the injector theory, and I replaced the sensor in the dpf.... still had the problem... replaced the dpf, was told that it "might be cracked", still, had the same problem and was considering replacing injectors... but first started carefully examining wires.... and found the "green" wire... replaced that turbo sensor... problem solved. Never had the high "dpf outlet temp" shut down code and corresponding vehicle shut down again.... These new emission controlled motors are prime candidates for starting wild goose chases... I've learned to study the wiring carefully, and reroute it when it lays up against something and vibrates, and to use additional loom, and wire ties....

 

And the trucks all perform basically the same with the same mpg figures? Has the mpg on the trucks improved since new, after the break in, does it stay consistent among all of them, and have you noticed any variance, or improvement in mpg after replacing a dpf? I'm curious about the egr valves, what kind of mileage are you seeing in relation to the egr valve replacement? In my experience a lot of dealership tech's will throw parts at a problem, hoping to fix it.... I stay away from the truck dealers and instead use one Detroit dealer. Anyway I gotta run, but good luck and I'll check back later