If price was not a consideration, Gas or Diesel?

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...

otrfun wrote:

DWeikert wrote:

otrfun wrote:

DWeikert wrote:

otrfun wrote:
rather than downshift when zero throttle is insufficient, it can then selectively apply reverse thrust or throttle (for lack of a better word) with the exhaust brake rather than downshift like a gas engine.

You're going to have to explain that one.

Maybe, "it can then apply variable amounts of reverse thrust or throttle . . . " might be a better way to phrase it, IDK. If that doesn't help, maybe someone else can chime in with a better explanation, sorry.

It sounds to me like you're saying the engine can inject a small amount of fuel long enough before the piston's TDC that it ignites and burns while the piston is still on the way up in the compression stroke. I was not aware any manufacturers had programmed that into their engines.

Sounds to me you may have a better "technical" (behind the scenes) understanding of how a diesel exhaust brake operates than I do. That's fine. My explanation was my best attempt to explain it from a "seat-of-the-pants" perspective to someone why may have never used one before. To me, it feels very similar to reverse thrusters being activated on an aircraft--no more, no less. Hopefully you did notice I qualified my explanation with "for lack of a better word". You're more than welcome to describe how it feels to you, or explain how this sensation is achieved from a technical perspective. I'm all ears--lol!

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...

time2roll wrote:
Price is no object would be an Earth Roamer. I believe these are diesel only.

Expedition vehicles are but I would be a bit wary of EarthRoamer

DWeikert wrote:

pnichols wrote:

However, since the exhaust braking engine back pressure mechanism is different than the gear braking engine back pressure mechanism ... maybe exhaust braking can somehow feel different to the driver. :h

The big difference is a gas engine just doesn't have the compression to slow down the vehicle like a diesel does. The transmission on a gas engine will take you into the high RPM's trying to compensate and still not do as good a job slowing the vehicle as the diesel at much lower RPM's.

Agreed

romore wrote:
After driving a diesel for 9 years I would rather fight than switch. I bought it for towing, not a grocery getter

Agree. Outside of the fact Gas engines do not exist in Pickups in Australia, Diesel is better for towing

DWeikert wrote:

otrfun wrote:

DWeikert wrote:

otrfun wrote:
rather than downshift when zero throttle is insufficient, it can then selectively apply reverse thrust or throttle (for lack of a better word) with the exhaust brake rather than downshift like a gas engine.

You're going to have to explain that one.

Maybe, "it can then apply variable amounts of reverse thrust or throttle . . . " might be a better way to phrase it, IDK. If that doesn't help, maybe someone else can chime in with a better explanation, sorry.

It sounds to me like you're saying the engine can inject a small amount of fuel long enough before the piston's TDC that it ignites and burns while the piston is still on the way up in the compression stroke. I was not aware any manufacturers had programmed that into their engines.

Sounds to me you may have a better "technical" (behind the scenes) understanding of how a diesel exhaust brake operates than I do. That's fine. My explanation was my best attempt to explain it from a "seat-of-the-pants" perspective to someone why may have never used one before. To me, it feels very similar to reverse thrusters being activated on an aircraft--no more, no less. Hopefully you did notice I qualified my explanation with "for lack of a better word". You're more than welcome to describe how it feels to you, or explain how this sensation is achieved from a technical perspective. I'm all ears--lol!

otrfun wrote:

DWeikert wrote:

otrfun wrote:
rather than downshift when zero throttle is insufficient, it can then selectively apply reverse thrust or throttle (for lack of a better word) with the exhaust brake rather than downshift like a gas engine.

You're going to have to explain that one.

Maybe, "it can then apply variable amounts of reverse thrust or throttle . . . " might be a better way to phrase it, IDK. If that doesn't help, maybe someone else can chime in with a better explanation, sorry.

It sounds to me like you're saying the engine can inject a small amount of fuel long enough before the piston's TDC that it ignites and burns while the piston is still on the way up in the compression stroke. I was not aware any manufacturers had programmed that into their engines. Getting a clean burn like that sounds very difficult.

Grit dog wrote:
^ Are you unfamiliar with what an exhaust brake does, or just commenting on the poster's description of the occurrence?

An exhaust brake basically closes off the exhaust flow so when the pistons try to push the gasses out of the cylinder during the exhaust stroke they're pressurizing the exhaust manifold between the cylinder and the exhaust brake. That pressure then serves to slow the engine creating a braking function.

How does that create a reverse thrust? Serious question.

DWeikert wrote:

otrfun wrote:
rather than downshift when zero throttle is insufficient, it can then selectively apply reverse thrust or throttle (for lack of a better word) with the exhaust brake rather than downshift like a gas engine.

You're going to have to explain that one.

Maybe, "it can then apply variable amounts of reverse thrust or throttle . . . " might be a better way to phrase it, IDK. If that doesn't help, maybe someone else can chime in with a better explanation, sorry.

^ Are you unfamiliar with what an exhaust brake does, or just commenting on the poster's description of the occurrence?