2021 Chevy Silverado 2500HD gas vs. diesel?

[MoKelly]

Mopar
Mokelly

Similar - but different.

MoKelly (Mo - Missouri, Kelly - Kelly)

MOPAR (Mo - Motor, Par - Parts)

MoKelly

 

[nisaacs]

I would have liked nothing better than not take my lumbering Diesel truck to go shopping. It is environmentally very irresponsible and selfish.

Yup, I see an electric truck and tractors in your future, to go with your electric gator....

If I could buy a diesel for my cordless hand tools, I would

 

[nisaacs]

And just because an engine has an engine accessory that another does not, doesn’t mean it’s more engine.

A semi auto .38 may have more components than a .357 magnum revolver, but it ain’t more gun lol.

I agree. I think the Cummins 5.9 has like 30% less moving parts than the competition, if it moves it is subject to wearing out. I test drove a Ford 6.0, 6spd manual one time and almost got killed trying to enter the main street (4 lanes). I stalled the engine like three times before I got it launched.

My Cummins trucks are launched at an idle at every stop, every time, loaded or empty. That's one of the reasons my clutches last so long. Back in the day before diesels, my big block gassers might go 50k miles before clutch time......

Back in the day, if you were serious about hauling heavy you bought a manual. The 3 and 4 speed autos were worthless, used behind a Cummins. With that said, I would really like to have a 4th gen Ram with a six speed auto, the autos have really come a long way. They are almost mandatory behind a gasser or v-8 diesel.

 

[deezler]

I mean a gas motor outlasting a diesel with both given equal use and care is actually laughable!
I guess I could try to explain to you that commercial and heavy use truck, farm tractors, etc. have diesel, not gas engines in them because they’re more durable than gas, but if that’s the way you think.....it would be a waste of my time. Lol

I got to hand to some of you, you keep the entertainment here at a high level of absurdity. Its cute, but absurd.
Never read so much disinformation and poor information in my life.

As someone who dyno tests the exact engines we are discussing on a daily basis, I find your position interesting and somewhat misinformed.

Commercial and heavy vehicles are primarily all diesel for the torque, and fuel economy. But there is no inherent reason why an internal combustion engine fueled with diesel will be more reliable long-term than one fueled with gasoline. The internal component structure is basically the exact same, as you probably know. I still see plenty of old big block gas dump trucks for sale around here... plenty reliable if you can tolerate 4 mpg. So you can easily design and produce a gasoline engine that will be very robust for hundreds of thousands of miles. But if you try to make a lightweight, low cost engine on EITHER fuel type, you're going to have durability problems long term. This is probably why you consider gas engines less reliable, because they were often intentionally underbuilt with the knowledge that they would NOT be chosen by people needing to work so hard on a daily basis.

Your thinking seems based on the last several decades of vehicle patterns in our country, which is totally logical. But consider the current, present reality. Gasoline engines today are better than they have ever been. Aside from some OEMs deciding to stick undersized and over worked turbocharged gas engines into heavy vehicles, we have new big displacement gas V8s that are designed and built for a lifetime of hard work, and dyno tested to prove this durability. And significantly better on efficiency (fuel consumption) than in the past, especially when coupled with our new transmissions.

Conversely on the diesel side, we now have emissions regulations that are putting the diesels competency into a shrinking box of reliability. Fuel pumps and injectors are operating at 40,000 PSI to inject fuel into the cylinder. And these poor components have to deal with ultra low sulfur fuel with greatly reduced lubricity. EGR systems pumping soot right back into your intake manifold. And the engine has breathe exhaust through a complex multistage emissions control system prone to failure. And even needing an extra fluid/fuel just to help control the output (DEF). The repair costs on the fuel injection and exhaust treatment system are ridiculous, as you likely know.

Meanwhile on a new large displacement gas engine.... things are still about as simple as they have ever been. Ford went back to pushrods, which was smart. Direct injection has allowed precise combustion control, enabling much better torque delivery at low revs. Sure, a 1000 lbf-ft diesel is still going to pull your trailer better. But how much speed do you need?

Personally, I am just glad we still have so many engine choices! We're probably in a golden era and peak of internal combustion engine development. R&D investment by OEMs is going to start declining, so enjoy your power and freedom now while you can.

 

[blee03]

Meanwhile on a new large displacement gas engine.... things are still about as simple as they have ever been. Ford went back to pushrods, which was smart. Direct injection has allowed precise combustion control, enabling much better torque delivery at low revs. Sure, a 1000 lbf-ft diesel is still going to pull your trailer better. But how much speed do you need?

Ford’s new gas 7.3 is 475ft lbs torque at 4000 RPM. I wouldn’t consider 4000 ‘low revs’

A 2012 Stock 6.7L Cummins is 800ft lbs at 1600 RPM

Everyone can go back and forth on this forever but until a gas engine isn’t running on gasoline, it will never be comparable to a diesel.

Gasoline doesn’t contain the stored energy that diesel does.

And if your running high RPM constantly in your gasser, that’s were the reliability comes into play. I’m not sure how many engines benefit from being run at high RPMs, but I’m guessing there isn’t many. (If any?)

How much speed do I need?
I would rephrase that to:

How much torque do you want?
Personally I would say, ”More”

The more torque produced down low in the RPM range, the easier to tow and less stress put on all the other pieces of the driveline, accessories, etc.

 

[deezler]

Ford’s new gas 7.3 is 475ft lbs torque at 4000 RPM. I wouldn’t consider 4000 ‘low revs’

Look at the actual power curve though. Might peak at 4000, but it's well over 400 lbf-ft at 2000rpm already. IE more than a Cummins 12V that used to be the holy grail. People seemed to drive dump trucks and haul heavy trailer loads with those back in the day just fine.... now we're in a crazy HP/Torque war in the diesels. Fun for me as an engineer in the industry, but pretty unnecessary for joe weekender.

Having a broader power band is actually an advantage that gasoline has over diesel, too.....

 

[Username Taken]

Kind of off subject, but I never give it a thought pulling off the highway in my 6.6 and shutting it off to get fuel. Should it have a cool down period for the turbo?

Yes, absolutely. Especially if you're working it. Your owners manual will even tell you that. The harder and longer you work it, the longer it needs to cool down.

When you're running your turbo hard, it's being cooled by air and by oil while turning 60,000 RPM.

You shut it off and that all stops. The oil quits running (although many now use a process to keep some oil running through it) and, more importantly, the massive amount of air that was flowing through it just stops.

Not good.

If, on your way home you have to go through a neighborhood and you're running it slow so as not crunch small things like squirrels, dogs and kids, that is usually okay if you weren't beating the daylights out of it.

Running down the road hard without a payload, you need to idle at the fuel pump for a couple minutes. Working it hard, you need to idle for several minutes of cool down.

 

[Username Taken]

Look at the actual power curve though. Might peak at 4000, but it's well over 400 lbf-ft at 2000rpm already. IE more than a Cummins 12V that used to be the holy grail. People seemed to drive dump trucks and haul heavy trailer loads with those back in the day just fine.... now we're in a crazy HP/Torque war in the diesels. Fun for me as an engineer in the industry, but pretty unnecessary for joe weekender.

Having a broader power band is actually an advantage that gasoline has over diesel, too.....

You're giving my Cummins an inferiority complex

 

[deezler]

^ Lol I doubt it. All you need is 10 minutes with a flash tuner to add a crazy HP/Torque boost anyway.

 

[nikerret]

Kind of off subject, but I never give it a thought pulling off the highway in my 6.6 and shutting it off to get fuel. Should it have a cool down period for the turbo?

I do this with any engine, especially, diesels.

My lawn mower has a small gas engine, mows at wide open throttle for the whole time I’m mowing. When done, I throttle back and let it run a minute, or so, at lower RPM, in the breeze.

My F-350 always gets 30 seconds to a minute of run time upon start up and before shut down. If I’ve run heavy, it cools longer. If possible, the ”cooling” phase starts before I get to my destination as it cools better while moving. Sometimes, this isn’t possible, like turning into a field, off the Highway. I’m not going to drive 20 MPH two miles from the entrance, I’ll drive normal and let it idle to cool, before shutting down.

With gas engines, there is a concern of cylinder wash, so I try not to let it idle too long, especially, on start up in freezing ambient temperatures. Cool down is a little less of an issue, due to everything being at (or close to) operating temperature. I don’t like to let it idle a long time, but I will if the task dictates (such as running off my external power leads).

My BX gets at least a minute of run time, before I move it. After the job is done, it gets 2-5 minutes cool down (depends on the job and ambient temperature). If it’s really hot, I’ll open the hood.

In the work F-350 with a 6.7L diesel, I do extended warm up and cool down, versus my person owned gas.

Keep in mind, some setups cool faster moving (most automobiles). The BX draws air from the passenger compartmen, moving is irrelevant, the radiator is on the wrong side. Others cool faster with the hood closed, dues to how the fan moves air over the engine.