blt2ski
Kirkland, Wa
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JRscooby wrote:blt2ski wrote:
I still believe for most interstate driving, a gas rig appropriately loaded, with current technology, will be fine into the low 20k realm.
The only thing a diesel will have generally speaking, is power at 10k feet vs the gas bring 30% down to to elevation. As I don't know if any diesels with out a turbo. With the advent of the eco boost style engines, elevation power loss will not be an issue.
Marty
Marty
I'm not sure if anymore I would declare "above X lbs, you need diesel"
but instead the decision would be based on miles per year. In the past, my thought was how much value is in a engine that will last 2-3 times the useful life of truck? but if drove enough miles/year the fuel savings would pay. But we have got to the point gas engines are lasting long enough that the rest of truck is likely to be reason to get rid of it. Meeting emissions standards with gas has improved efficiency and the parts needed to do it have proven pretty trouble free. The same can't be said about diesel, and cost to repair can exceed value of pickup.
Scooby
Being as Ive seen a number of F750 rigs run by Wa ST mostly DOT rigs. I do believe that gas vs diesel should come down to the how many miles you drive etc. Iis gone from 15-20k miles a year, 80-100k miles to pay for the increased cost of a diesel, to 150-200+k miles, and 30k+ miles a year. This is assuming a 3-5 year ROI on the diesel.
These bigger gas motors have a place in the under 30k gvwr/gcw rigs running down the road.
I pointed out the exhaust brakes in the Isuzu's I've driven since early 80's, as something that's been around awhile too. With some jurisdictions outlawing "Jake brakes", IE the use of velves to get compression braking, exhaust valves do a similar effect. With out the noise issue.
I've have heard about them on gas rigs, I'm going to assume one can still get use out of it. Whether it's as good as used on a diesel. That I don't know.
Marty
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JRscooby
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Quote: With some jurisdictions outlawing "Jake brakes", IE the use of velves to get compression braking, exhaust valves do a similar effect. With out the noise issue.
I had a couple of mid '70s Macks, 1 had factory installed jake, the other had add on exhaust brake. Driving and maintaining them, I can say for sure they don't really have similar effect. Jake far and away better.
In the HD market, for likely 25 years a compression brake has become pretty standard. And while the laws about compression brakes are on the books most engines make about the same noise pulling hard as slowing. Inside cab noise standards might of caused a redesign. And most operators understanding the engine is designed to work best with mufflers also reduces that problem.
On this site, any time somebody asks about using spark plug engine to move their RV, 1 of the next 3 replies will be YOU WILL BE IN THE TRUCK LANE ALL THE TIME! In a day's drive, the time spent going up or down a steep enough to really slow you will not reduce average speed by much. Either most can't do the math, or the fact somebody passes them is a insult to manhood.
With all the issues with diesel emission systems, and cost to repair, not sure I would want to go that way.
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Me Again
AZ - Summer in NW WA
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JRscooby wrote:Quote: With some jurisdictions outlawing "Jake brakes", IE the use of velves to get compression braking, exhaust valves do a similar effect. With out the noise issue.
I had a couple of mid '70s Macks, 1 had factory installed jake, the other had add on exhaust brake. Driving and maintaining them, I can say for sure they don't really have similar effect. Jake far and away better.
In the HD market, for likely 25 years a compression brake has become pretty standard. And while the laws about compression brakes are on the books most engines make about the same noise pulling hard as slowing. Inside cab noise standards might of caused a redesign. And most operators understanding the engine is designed to work best with mufflers also reduces that problem.
On this site, any time somebody asks about using spark plug engine to move their RV, 1 of the next 3 replies will be YOU WILL BE IN THE TRUCK LANE ALL THE TIME! In a day's drive, the time spent going up or down a steep enough to really slow you will not reduce average speed by much. Either most can't do the math, or the fact somebody passes them is a insult to manhood.
With all the issues with diesel emission systems, and cost to repair, not sure I would want to go that way.
I owned a 1993 RAM diesel, a 2001.5 RAM diesel, and a 2015 RAM diesel, and loved all three for vary reasons. The 2015 with Aisin transmission was a great towing machine at 24,500 combined weight. The BANKS exhaust brake I put on the 2001.5 worked great for the 12K+ load I towed with that truck for 14 years.
* This post was
edited 10/24/23 03:33pm by Me Again *
2021 F150 2.7 Ecoboost - Summer Home 2017 Bighorn 3575el. Can Am Spyder RT-L Chrome, Kawasaki KRX1000. Retired and enjoying it! RIP DW 07-05-2021
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FishOnOne
The Great State of Texas
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Here's a pretty good tow with a 7.3 and 3.73 gears.
Link
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JRscooby
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Quote: The BANKS exhaust brake I put on the 2001.5 worked great for the 12K+ load I towed with that truck for 14 years
There is no doubt exhaust brakes work. If you do turn it off, then back on while going down a hill. And nobody that has ever compared can say diesel, with no exhaust brake, or it not functioning, will claim gas engine does not slow more.
What nobody wants to compare is normally functioning gas engine to like sized and loaded diesel with exhaust brake.
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Grit dog
Black Diamond, WA
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JRscooby wrote:Quote: The BANKS exhaust brake I put on the 2001.5 worked great for the 12K+ load I towed with that truck for 14 years
There is no doubt exhaust brakes work. If you do turn it off, then back on while going down a hill. And nobody that has ever compared can say diesel, with no exhaust brake, or it not functioning, will claim gas engine does not slow more.
What nobody wants to compare is normally functioning gas engine to like sized and loaded diesel with exhaust brake.
Except that’s what is actually being compared.
Of course diesels without exhaust brakes, James, retarders have squat for compression braking. It’s just a function of their design. And since all the Hd pickup diesels have had VVTs for well over a decade, it’s now just a standard feature.
Comparing a light duty class 2-3 or even class 4-5 diesel with a functional exhaust brake (Cummins at least, I’ve pulled with a LML Duramax and it was meh, better than nothing, never towed with a 6.7 Powerstroke of any flavor) is no contest.
I can roll down a 6% with a 6ton trailer behind the ole 4th Gen and basically never touch the brakes unless I want to call up a downshift, but I’m usually in manual anyways, and a new 10 speed gasser pulling my boat of about half the weight is on the hooks multiple times.
It’s not even an apples to apples comparison as the exhaust brake will win 10 times out of 9.
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Me Again
AZ - Summer in NW WA
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JRscooby wrote:Quote: The BANKS exhaust brake I put on the 2001.5 worked great for the 12K+ load I towed with that truck for 14 years
There is no doubt exhaust brakes work. If you do turn it off, then back on while going down a hill. And nobody that has ever compared can say diesel, with no exhaust brake, or it not functioning, will claim gas engine does not slow more.
What nobody wants to compare is normally functioning gas engine to like sized and loaded diesel with exhaust brake.
The Cummins for some unknown reason pretty much freewheel without the exhaust brake on, where as the V8 Duramax and Powerstroke provide a degree of grade braking.
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JRscooby
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Grit dog wrote:
Except that’s what is actually being compared.
I can roll down a 6% with a 6ton trailer behind the ole 4th Gen and basically never touch the brakes unless I want to call up a downshift, but I’m usually in manual anyways, and a new 10 speed gasser pulling my boat of about half the weight is on the hooks multiple times.
It’s not even an apples to apples comparison as the exhaust brake will win 10 times out of 9.
Where is it compared? When have you used a gas engine, with same displacement, on same hill with same load?
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FishOnOne
The Great State of Texas
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Me Again wrote:JRscooby wrote:Quote: The BANKS exhaust brake I put on the 2001.5 worked great for the 12K+ load I towed with that truck for 14 years
There is no doubt exhaust brakes work. If you do turn it off, then back on while going down a hill. And nobody that has ever compared can say diesel, with no exhaust brake, or it not functioning, will claim gas engine does not slow more.
What nobody wants to compare is normally functioning gas engine to like sized and loaded diesel with exhaust brake.
The Cummins for some unknown reason pretty much freewheel without the exhaust brake on, where as the V8 Duramax and Powerstroke provide a degree of grade braking.
My Powerstroke with the 6 speed freewheels a lot when coasting. I actually feel no resistance when coasting.
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Lantley
Ellicott City, Maryland
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"Where is it compared? When have you used a gas engine, with same displacement, on same hill with same load?"
It's kind of a mute point. The exhaust brake has become a standard feature on HD diesels. A feature that works well and is a real difference maker.
A feature that HD gassers simply don't have. There is no comparison to be made.
We don't need to get into load, displacement or any other factor.
The gasser does not have an exhaust brake. Ultimately no exhaust break is a deal breaker and a major shortcoming of a gas engine
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