If price was not a consideration, Gas or Diesel?

I wonder when (if ever) trucks are going to have solenoid operated valves?

Closing both intake and exhuast valves automatically whenever needed on downgrades would probably provide very powerful compression braking in gas engines.

Regarding exhaust brakes:

Gas engines have a throttle so provide a certain amount of restriction natively. This acts somewhat like a brake.

Diesels without exhaust brakes have little natural compression braking since they only have the friction of the spinning engine and no restriction in the airflow to slow them down.

Now with exhaust-restricting turbos you can add significant resistance to the coasting engine.

Here is the big difference between restricting the intake (gas engine throttle) and restricting the exhaust (diesel exhaust brake): With an intake restriction you can only pull down to as low as a perfect vacuum which is less than 15psi. On the exhaust side you can build much higher pressure than that which provides a much stronger braking effect because it takes more energy to build higher pressures.

Kayteg1 wrote:

otrfun wrote:
... FWIW, I've heard you can get a DPF cut-open, cleaned, and welded back together for about a 1/3 the cost of a new one.

That would be technique used by butcher.
DPF cleaning follows up the technology and now in any bigger US city you will find a shop who does ultrasonic cleaning.
In Europe they have several different techniques - from plain water pressure flushing to use of solvents . . .

Glad technology has moved us past the need to butcher DPF's--lol! Seriously though, it's good to know there are other options available if/when a DPF fails. Thanks.

The extended warranty Sold to me at time of purchase does not cover emissions equpiment...Though at the time I bought it more as computer insurance....After a collection of nagging issues from my first 07 6.7 to my 16, I can’t hardly help but to wait for the other shoe to drop...Fair or not, I can only consider the emissions add-ons as Beta engineering...

otrfun wrote:
... FWIW, I've heard you can get a DPF cut-open, cleaned, and welded back together for about a 1/3 the cost of a new one.

That would be technique used by butcher.
DPF cleaning follows up the technology and now in any bigger US city you will find a shop who does ultrasonic cleaning.
In Europe they have several different techniques - from plain water pressure flushing to use of solvents.
But from my (so far limited) experience - the main issue with DPF is shutting the engine off with unfinished regeneration process.
For some reasons manufacturers did not include any indication of regeneration, what is big issue with vehicles used for short commute, but now ScanGauge made X-gauges who will show regeneration status and soot %.
That is great help in keeping DPF healthy for life of the engine.
And again- Ford made very advanced WI-FI truck connection, where my truck talks to headquarters behind my back, what results in monthly health reports, but those reports don't include DPF status.
Go figure.
So in my final conclusion, DPF might not be the best technology on the market and some countries already legalized DPF delete, but that doesn't change the facts about diesel superiority.
Soon gasoline engines will have to reach next low emission levels and who knows how that will go?

Gas

otrfun wrote:

3 tons wrote:
IMHO, a diesel engine is hands down superior in a truck pulling or carrying a heavy load, but to be objective about it one must consider (at least under the U.S. EPA rules) the life expectancy of the diesel’s individual emissions devices and the associated cost of replacement once the factory warranty expires...Oddly, I never see this important aspect a part of these discussions...

The post warranty replacement (at who knows what mileage ??) of a sooted-up turbo, DPF, SCR, EGR Cooler/valve, and uber costly injectors don’t come cheap (from nasty experience...) and should be factored in when considering the true reliability and longevity of a diesel...Just Saying...

x1. I might add, at least with the Ram Cummins, the OEM extended warranties do not cover the DPF and several other emission devices. Once the emissions warranty expires (8yr/80k??) you're on your own. I believe it costs $2k - $4k to replace a DPF or SCR. A 3rd party warranty may be a better option if you want coverage on these items. FWIW, I've heard you can get a DPF cut-open, cleaned, and welded back together for about a 1/3 the cost of a new one.

Great point Sir, I have little doubt that the core engine component of most diesels is capable of lasting 300 + miles without issue, but as you correctly stated it cost a small fortune to have these various emission devices replaced and I’ve had several fail (some under warranty, some not - $$), beginning at about 70k miles... From my perspective DEF has made things better, but nowadays these gremlins should also be considered when fairly comparing gas to diesel...Depending on one’s hauling needs, diesel may still be justifiable...JMO

3 tons wrote:
IMHO, a diesel engine is hands down superior in a truck pulling or carrying a heavy load, but to be objective about it one must consider (at least under the U.S. EPA rules) the life expectancy of the diesel’s individual emissions devices and the associated cost of replacement once the factory warranty expires...Oddly, I never see this important aspect a part of these discussions...

The post warranty replacement (at who knows what mileage ??) of a sooted-up turbo, DPF, SCR, EGR Cooler/valve, and uber costly injectors don’t come cheap (from nasty experience...) and should be factored in when considering the true reliability and longevity of a diesel...Just Saying...

x1. I might add, at least with the Ram Cummins, the OEM extended warranties do not cover the DPF and several other emission devices. Once the emissions warranty expires (8yr/80k??) you're on your own. I believe it costs $2k - $4k to replace a DPF or SCR. A 3rd party warranty may be a better option if you want coverage on these items. FWIW, I've heard you can get a DPF cut-open, cleaned, and welded back together for about a 1/3 the cost of a new one.

3 tons wrote:
IMHO, a diesel engine is hands down superior in a truck pulling or carrying a heavy load, but to be objective about it one must consider (at least under the U.S. EPA rules) the life expectancy of the diesel’s individual emissions devices and the associated cost of replacement once the factory warranty expires...Oddly, I never see this important aspect a part of these discussions...

The post warranty replacement (at who knows what mileage ??) of a sooted-up turbo, DPF, SCR, EGR Cooler/valve, and uber costly injectors don’t come cheap (from nasty experience...) and should be factored in when considering the true reliability and longevity of a diesel...Just Saying...

My 07 Duramax had 300K on it when I traded it in. It required a water pump and starter. Otherwise no major engine repairs.
Sure anything can break but that's another topic. The parts you mentioned are not guaranteed to fail.
Also consider gas engines are not immune from repairs and also have the potential for failures.

DWeikert wrote:
No worries. My wording may have been a little blunt in the original question, and for that I apologize. Exhaust brakes can also regulate the amount of back pressure which has the effect of adjusting the amount of braking. I wonder if what you're feeling is the change from partial braking to full.

As I said, my Duramax uses the turbo vanes to simulate a separate exhaust brake. I know what I've felt in that going down grade is initially I have just engine braking holding me back, which is only enough to slow me down on shallow grades. If I just tap the brakes the exhaust braking then kicks in. And there, I'll agree, it has the feeling of an aircraft applying reverse thrust, but it's really just the switch over from the weak engine brake to much stronger exhaust brake.

At least, that's what I think is going on...

Just a case of semantics. I chose the visceral approach. You chose technical. IMO, both are equally important.