Gas vs. Diesel, 3.73 vs. 4.10, 2500 vs. 3500

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Irishthreeper

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My deezel gets 45 mpg towing a 37,000 lb trailer…
Just kidding, I have a Hemi :)
 

BossHogg

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Your 24 mpg must be an evic reading. Others I know do more like 21 mpg hand calculating.
Hand calculations introduce their own errors. Because fuel is sensitive to expansion and contraction and not really knowing what variance between fill-ups. A couple of tenths delta between fill-ups has an impact on the resulting MPG.

I can not do hand calculations because my driving is mixed towing (boat, utility trailer, dump trailer, and fifth wheel RV). What I do, is reset the average MPG on the DIC and do my driving and use that number. It isn't perfect but it is ideal for comparison on the same vehicle.

The point I was making isn't my actual MPG, we all know that varies between drivers, but the difference between the cost to drive a gas versus diesel with respect to cost per gallon. The MPG I get on my 3500 is first-hand knowledge. The MPG I used for the HD Hemi is what I've read on the forums. I really didn't want this to go into an MPG debate. It is about a driver and which powertrain is best for him. My comment was about someone stating they are glad they have a Hemi because diesel is more expensive, I was pointing out that this may not be true when viewed through a different facet.

Using your 21 MPG, the diesel still comes out less expensive to drive per mile than the Hemi HD. Comparing the Cummins to the Hemi in a towing situation, the cost per mile of travel will strongly favor the diesel since it is simply more efficient, diesel has more chemical energy per ounce than gas. Couple that with an in-line 6 cylinder long stroke that has the ability to take full advantage of diesel's combustion characteristics.
 
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sandawilliams

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Hand calculations introduce their own errors. Because fuel is sensitive to expansion and contraction and not really knowing what variance between fill-ups. A couple of tenths delta between fill-ups has an impact on the resulting MPG.

I can not do hand calculations because my driving is mixed towing (boat, utility trailer, dump trailer, and fifth wheel RV). What I do, is reset the average MPG on the DIC and do my driving and use that number. It isn't perfect but it is ideal for comparison on the same vehicle.

The point I was making isn't my actual MPG, we all know that varies between drivers, but the difference between the cost to drive a gas versus diesel with respect to cost per gallon. The MPG I get on my 3500 is first-hand knowledge. The MPG I used for the HD Hemi is what I've read on the forums. I really didn't want this to go into an MPG debate. It is about a driver and which powertrain is best for him. My comment was about someone stating they are glad they have a Hemi because diesel is more expensive, I was pointing out that this may not be true when viewed through a different facet.

Using your 21 MPG, the diesel still comes out less expensive to drive per mile than the Hemi HD. Comparing the Cummins to the Hemi in a towing situation, the cost per mile of travel will strongly favor the diesel since it is simply more efficient, diesel has more chemical energy per ounce than gas. Couple that with an in-line 6 cylinder long stroke that has the ability to take full advantage of diesel's combustion characteristics.
Gotcha
 

HEMIMANN

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Diesel Fuel is taxed higher than gasoline because all large trucks are diesel-powered, and vehicle weight is what damages roads. So the vehicles doing the most damage are taxed higher. The fact that diesel engines have since been put into small vehicles is irrelevant to government taxation policy.
 

KKBB

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Diesel Fuel is taxed higher than gasoline because all large trucks are diesel-powered, and vehicle weight is what damages roads. So the vehicles doing the most damage are taxed higher. The fact that diesel engines have since been put into small vehicles is irrelevant to government taxation policy.
Except in the midwest where there are huge farm equipment damaging our roads that don't pay a penny in taxes!!!
 

HEMIMANN

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Except in the midwest where there are huge farm equipment damaging our roads that don't pay a penny in taxes!!!

Their primary use is in the fields, not on the roads. I live in the midwest.
 

KKBB

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Their primary use is in the fields, not on the roads. I live in the midwest.
I get that, but they use the highways to get where they are going and it destroys the highways way more than all the small cars and trucks driving on them.
 

BossHogg

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Diesel Fuel is taxed higher than gasoline because all large trucks are diesel-powered, and vehicle weight is what damages roads. So the vehicles doing the most damage are taxed higher. The fact that diesel engines have since been put into small vehicles is irrelevant to government taxation policy.
The taxation would be justifiable if, and I mean if the tax money went to roads but it doesn't. You can check a source like gas buddy to see what the fuel tax rate is but you will need to look within your own state to see where the fuel tax money goes. Some does go to roads but very little.
 

HEMIMANN

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The taxation would be justifiable if, and I mean if the tax money went to roads but it doesn't. You can check a source like gas buddy to see what the fuel tax rate is but you will need to look within your own state to see where the fuel tax money goes. Some does go to roads but very little.
Federal Tax does.
 

dhay13

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We have the 3rd highest gas tax here in PA (.77/gallon). This tax is supposed to be for fixing bridges and roads yet a few months ago we had a bridge collapse here in Pittsburgh and the topic came up. There was an audit a few years ago and they said that something like $4B came up missing. The state is claiming it went to pay state police salaries and want to raise taxes again so they can put it towards fixing bridges and roads...lol
 

BossHogg

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Federal Tax does.
The federal fuel tax, .184 per gallon, goes into a fund that is marked for infrastructure projects which includes mass transit. 40% of the nation's roadways are in disrepair. Never trust a politician with taxpayer money. It starts out going where it is supposed to but over time, it slowly gets diverted. Remember the lottery proceeds when states started introducing state lotteries, the majority of lottery proceeds went to education, now very little goes that way and most of the money goes into the general fund.
 

dhay13

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The federal fuel tax, .184 per gallon, goes into a fund that is marked for infrastructure projects which includes mass transit. 40% of the nation's roadways are in disrepair. Never trust a politician with taxpayer money. It starts out going where it is supposed to but over time, it slowly gets diverted. Remember the lottery proceeds when states started introducing state lotteries, the majority of lottery proceeds went to education, now very little goes that way and most of the money goes into the general fund.
I live in a small town of about 8000 with about 10 police officers. Our town owns the electric dept so we pay .18/kwh (about 30-40% higher than usual). That rate is so high as they use that money to fund the police dept. Our top paid officer last year made $170,000 and I think every full timer made over $100,000. And they do not investigate any serious crimes. Anything involving death they call the state police in (even car accidents). We have tried to fight this but they said the only way around it is to disband the police dept. I bought a house several years ago and went to get the electric turned on and they told me I had to pay the past bill from the previous owner first ($227). I refused and called the PA PUC (public utilities commission) and they told me that was illegal. They then asked me who my electric provider was and when I told them they responded saying they had no authority over them and they could do what they wanted. Most businesses have moved because electric was more than rent
 

Bearcatrp

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Not only will you not be climbing hills as well but you may want to take another look at the fuel costs even though gas is a buck less than diesel. Comparing the cost of fuel on the surface is shocking, in this example, a dollar more per gallon, what has to be compared is the cost per mile to drive a gas-powered vehicle to a diesel-powered vehicle of the same type.

From what I read, most are claiming around 15 MPG empty on a RAM Hemi HD. I have a RAM 3500 Cummins, SRW, 3:42 axle ratio and I average 24 MPG empty.

If gas is $4.39 per gallon and the vehicle is getting 15 MPG, the cost to drive 1 mile is $0.293
If diesel is $1 more than gas and the vehicle gets 24 MPG, the cost to drive 1 mile is $0.225

If the vehicle has a 32-gallon tank, the range of the diesel is 288 miles greater than the gas HD at a fuel savings of $18.30Politicians know this and in most states diesel is more heavily taxed than gas causing the higher cost of diesel at the pump. Also, fewer vehicles use diesel and the objections from the masses are not

The need for a diesel-powered vehicle falls to the choice of need and want. I needed a diesel 3500 to pull 16,000 pounds of RV around our beautiful country. I recently purchase a new 2022 ECOdiesel, I wanted it. The 2022 replaced my 2013 Hemi which yielded a pitiful 17 MPG average. The ECOdiesel is coming in at 26 MPG average and the ECOdiesel was an upcharge of $2,200. At current fuel pricing, the ECOdiesel will break even at 41,000 miles.
so what’s your MPG pulling 10,000 lbs plus with that gear ratio?
 

BossHogg

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so what’s your MPG pulling 10,000 lbs plus with that gear ratio?
Keep in mind, MPGs are very subjective. For example, when I drove my wife's 2008 Tahoe for any length of time, I averaged just over 3 MPG higher than when she drove, different driving styles.

Pulling our Montana 3790RD fifth wheel, 3,100 pin weight, 16,000 pounds wet, I get between 8 and 14 miles per gallon. The reason for the large delta is primarily wind load. If I am driving into the wind it hurts but if I have a strong tailwind I win. I also don't exceed 65 MPH, that is the tire rating, and I have no issue obtaining 65 MPH on a freeway acceleration ramp.

Pulling my boat which is a 19-foot outboard, about 5,000 pounds wet, and little surface area for wind loading, the 3500 Cummins will average 18 MPG. I should also note that my driving offers reduced stop/go simply because of the ruralness of where I drive.

I think people get overly hung up on axle ratios, just like they do over oil brands, battery brands, battery chemistry, octane, and dozens of other automotive-related products. Sometimes we forget the transmission and tire circumference plays heavily into vehicle performance along with the axle ratios. Take a popular argument on the RAM 1500 forums about 3:21 versus 3:92 ratios. Nobody stops to think that the older RAMs that had the 6-speed transmission with 3:92s had less off-the-line grunt than the newer 8-speeds equipped with 3:21 axle ratios. The output ratios of the transmission played heavily into that.

When it comes to selecting an axle ratio, I define my goals. Am I going to be pulling at near tow capacity in largely stop and go driving or am I an occasional tower, or more frequent and only towing a mid-capacity load. Perhaps I'm a younger driver and want the jackrabbit launches.

I did do a test on my 3500 while pulling the Montana, it was an MPG test at 65 MPH with 6th gear locked out. While the RPMs were higher than it is in 6th gear, both 5th and 6th had the Cummins in its RPM powerband. What was interesting, over time, the MPGs were the same. I guess the laws of physics are true.
 

06 Dodge

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I get that, but they use the highways to get where they are going and it destroys the highways way more than all the small cars and trucks driving on them.
I just moved from northern Iowa and know that 99% of all grain wagons were over weight thus they can leave ruts in asphalt on warm days & big ruts on gravel roads.
 
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