DEF going away ?

[ptsg]

This was the state of the intake manifold on our 2016 SUV after only 87,000 miles, thanks to the good ol'EGR. No codes yet, just preventative maintenance. The cylinder head wasn't any better as you can imagine.

Before:

After:

Surely, making an engine eating it's own cr@p can't do it any good?

This vehicle also adds extra fuel on the exhaust stroke when doing an active regen, which happens to be every 150 miles, more or less. This is done to increase the temps of the DPF.

Of course, when it regens and I happen to be doing city driving, a lot of that fuel will end up washing down the cylinder walls and contaminate the oil.

I've pretty much cut the service intervals from 12,000 miles to about 7,000 miles, so I'm not running that contaminated oil for so long. I've also had to send the DPF for cleaning at only 56,000 miles. Turned out to a close to $1000 ordeal.

Not only the emissions equipment is not reliable, it also trashes the reliability of the engines. All of that while using more fuel.

I'm just glad my 2010 pickup was about the last one on the assembly line to come out without a DPF. Just a small and so far, trouble free catalytic converter. I've had to replace the EGR cooler though. Imagine that.

 

[Snobdds]

Lol. I appreciate the anecdotal pieces of evidence.

Was just trying to share the perception from the engineering side...

The engines are all robust, at this point. The Cummins X15 hasn't changed much in years - It does just fine loping along at 1200rpm low load, indefinitely. The challenge comes when you need to integrate a comprehensive exhaust aftertreatment system onto it.

For what its worth, I feel like I am noticing a pattern with Paccar and DPF/DEF/SCR issues. The aftertreatment system isn't always engineered or integrated by the engine manufacturer (which is dumb).

You are the first person in the diesel world to tell me lugging an engine is fine.

What?

 

[Shawn T. W.]

No reason to bash the aftertreatment system that is keeping our air clean

This is my solution to clean air ... I moved from my townhouse on a golf course in Arizona, to the country in Missouri ... Clean fresh air, lots of it!

"The solution to pollution is dilution!"

My point is we as a county have done so much already (too much!) to try to clean up the air, and yes in the cities there is less smog, but until the rest of the world even tries to catch up, we are peeing in the ocean to try to get the tide higher! India and China, are you listening?

And @Snobdds the part ...

It does just fine loping along at 1200rpm low load

That's pulling 75,000 - 80,000 Lbs ... ! Low load???? That engine is STRUGGLING!

 

[Hay Dude]

My 2007 International HT570 only has cooled EGR and it was a mess, too. Most people only think of DEF/DPF.

IMO, and the opinions of many other farmers & truckers I know, only the engineers and the salespeople from the DEF/DPF producers think they’re “great”.
Most all us farmers & truckers think it’s JUNK.

 

[JRH02]

Clean fresh air, lots of it!

You and I agree there. And add water too if you can.

 

[dnw64]

The Cummins X15 hasn't changed much in years - It does just fine loping along at 1200rpm low load...

Never drove a class 8 truck*, so maybe...

My 8000# F250 with 465 lb/ft and 435 HP does fine "loping along at 1200rpm", but as soon as I add even just 10,000# it's a different story. Granted, it's a gasser, but power doesn't care where it comes from.

*actually, I may have, once - in a yard. My father-in-law was trying to "man me up" by learning to operate heavy equipment. First it was a '70s C70(?) with a 2-sp rear end, then an ancient bulldozer, a somewhat older backhoe and a relatively modern excavator (all this in about the early '90s - he passed away in 1994).

 

[deezler]

Yes the engines are robust.

But that’s not what you said. You said the emissions systems were “robust and reliable”.

But they aren’t. That’s why one of mine was turned off by the previous owner. We have crops to make. Spending time with a laptop & sensor replacement hinders that process too much.

I don't recall how I worded it but what I meant to imply, and is still just clearly true, is that the emissions systems technology is robust and reliable. From a functional engineering perspective, it is incredibly easy and straightforward to catch particulates in a DPF that periodically initiates a regeneration based upon differential pressure sensors. From the same perspective, it is incredibly easy and straightforward to inject DEF into an SCR to convert smog-forming oxides of nitrogen into harmless water and nitrogen. These technologies were chosen for diesel engine emissions compliance precisely because they are easy and reliable.

So what do you need to make this all work seamlessly for the end user? A competent integration to the vehicle, engine (and transmission if we want to lump that in) in terms of equipment sizing, controls, sensors, and of course quality manufacturing.

What vehicles have problems on the road? The ones where the vehicle manufacturer cut corners and chose low-cost suppliers, and/or didn't do their proper engineering on sizing and controls of the aftertreatment components. Where you find actual problems in the field tend to be on lower-margin vehicles, or low-volume vehicles that simply don't warrant the necessary investment in engineering and system validation. Why do we see so many threads about LS tractors having DPF issues here? Because LS sucks at engineering and is intentionally producing a low cost product.

What vehicles don't have hardly any issues at all? The highest volume products with the most at stake. Think your Ford 6.7, duramax, Cummins ISB. People are still buying diesel HD pickup trucks in record volumes because the emissions compliance technology works seamlessly (in general), and certainly well enough not to deter buyers. It simply just works fine, and keeps our air much cleaner.

So if your truck is having issues on the road, its basically because your manufacturer just sucked at integration, controls, or cut costs. My 2c: blame them, not the regulations. Because for most of us, it all works just fine and is well worth having in place. Thus, the regulations will remain. Do your homework and research, buy what works.

 

[deezler]

You are the first person in the diesel world to tell me lugging an engine is fine.

What?

Yep, lug away. Modern internal combustion engines can run fine at any speed and load combination. We test them across the full load and speed range, in a variety of durability and endurance cycles, but also steady state mapping, including checking things like real-time oil consumption, blow-by, efficiency, internal friction and more.

Basically, it's up to the operator. Run it however you want; but ideally paying attention and listening/feeling to your engine performance. And of course performing all required maintenance on time.

 

[deezler]

That's pulling 75,000 - 80,000 Lbs ... ! Low load???? That engine is STRUGGLING!

No, it's not. Not at all, honestly.

https://www.cummins.com/engines/x15-performance-series-2024

A Cummins X15 makes full torque at just 1,000rpm. Depending on your X15 rating, it can already be making over 400HP at 1200rpm. To pull 80,000 lbs on flat ground at highway speed, you only need 150-200 HP depending on your aerodynamic profile. So cruising along at 1200 rpm, you are normally under 50% load with lots of extra power/torque available for hills or passing. And of course, you can downshift to get to peak power as needed.

Modern HD diesel engines are a real marvel of engineering. I'm privileged to get to dyno test them daily.

 

[deezler]

600HP diesel engines are great….especially when diesel fuel is $4.39 a gallon
Easy to see you don’t own a business…

Pop quiz: which engine uses more fuel cruising along at a steady 65 mph with the same load: a 400HP X15 or a 600HP X15?

Answer? They use the exact same amount of fuel. The internal frictional losses are exactly the same (we supply the exact same pistons and rings inside the engine regardless of rating). A 600HP X15 only uses more fuel than a 400HP X15 when you go above 400HP with it (IE, accelerating). If your drivers are hot rodders, sure, their mpg will suffer. Otherwise, no difference.

This is why I love tuning all my personal turbocharged vehicles for more power; it doesn't change the fuel consumption at all in the real world. Only when you use that extra power do you use extra fuel (a tiny fraction of the time for a passenger vehicle - but certain semi truck routes could definitely get into more noticeable situations).