Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 07-26-2014, 01:17 PM   #1
Full Time Adventurer
 
BoldAdventure's Avatar
 
2007 27' International CCD FB
Nomadic , USA
Join Date: Jul 2013
Posts: 2,748
Exclamation InfoGraphic: Actual Fuel Economy of Diesel vs Gas Towing

Thought I'd share:

__________________
Family of 5 exploring the USA with a Ram Power Wagon & Airstream in tow.
OUR BLOG | INSTAGRAM
BoldAdventure is offline   Reply With Quote
Old 07-26-2014, 02:02 PM   #2
Rivet Master
 
gandttimes's Avatar
 
2014 25' FB International
2007 20' Safari SE
2005 19' Safari
Qualicum Beach , British Columbia
Join Date: Sep 2004
Posts: 1,096
Quote:
Originally Posted by BoldAdventure View Post
Thought I'd share:
Can you post the link? Can't read it on either of my devices and it looks like an interesting read.
gandttimes is offline   Reply With Quote
Old 07-26-2014, 07:18 PM   #3
Rivet Master
 
1981 31' Excella II
New Market , Alabama
Join Date: Sep 2011
Posts: 6,145
Does this figure in higher initial costs and added maintenance costs as well? I will gladly pay the extra $10 for 1000 miles in a gaser.

Perry
perryg114 is offline   Reply With Quote
Old 07-26-2014, 07:59 PM   #4
Rivet Master
 
rodsterinfl's Avatar

 
2006 25' Safari
St. Augustine , Florida
Join Date: Oct 2011
Posts: 2,670
Images: 10
Quote:
Does this figure in higher initial costs and added maintenance costs as well?

Obviously not since the information is only consumption and efficiency. It confirms what I believe, that a price-conscious consumer would not buy a diesel unless absolutely necessary and that newer gassers are as efficient.

The only oddity I see is in trailer length to mpg. Why does a 21-25 travel trailer require more gas than a 26-40 foot? Could it be in the number of respondents? If you average all travel trailer lengths, the mpg figure is 12mpg towing a travel trailer. Hmm. Dead on for me.
__________________
WBCCI 8653/AIR 60240
2022 Ford F150 PowerBoost Platinum w/7.2KW
rodsterinfl is offline   Reply With Quote
Old 07-26-2014, 08:15 PM   #5
Rivet Master
 
Al and Missy's Avatar
 
2002 30' Classic S/O
Fleming Island , Florida
Join Date: Nov 2013
Posts: 4,667
Rodster,
I'm guessing that the proportion of trailers towed by diesels is higher for the bigger trailers and that drives up the average mileage for them.

Just a guess.

Al
__________________
“You cannot reason someone out of a position they have not been reasoned into"
Al, K5TAN and Missy, N4RGO WBCCI 1322
2002 Classic 30 Slideout -S/OS #004
2013 Dodge 2500 Laramie 4x4 Megacab Cummins
Al and Missy is offline   Reply With Quote
Old 07-26-2014, 08:25 PM   #6
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
It is really simple math at first, diesel has 113% the energy content of gas by volume.

If diesel costs more than 113% that of gas it is less economical from the get go.

Then we have to consider up front cost, loss of efficiency due to greater vehicle weight, and the cost of routine maintenance and repair.

For a pickup truck I practically guarantee that the cost of ownership plus fuel is higher for a diesel.


Sent from my iPhone using Airstream Forums
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-26-2014, 08:31 PM   #7
2 Rivet Member
 
ARLINGTON , Texas
Join Date: Sep 2008
Posts: 41
It would be nice to know what year model Duramax they used for testing, because my 2011 gets considerably better mileage than what they show for an unloaded truck. The mileage show for a loaded 34' travel trailer of about 12-14 is in the range of what I actually get. But was a good read for comparison sake.
HighFlying is offline   Reply With Quote
Old 07-26-2014, 08:32 PM   #8
Rivet Master
 
2005 19' Safari
GLENDALE , AZ
Join Date: Aug 2004
Posts: 2,453
These graphs are very interesting. However, we have a Toyota Tundra, and 8 mpg is way off with respect to our mileage, even considering our Bambi is only 19' long. We have never gotten less than 11-12 mpg per tank, and our average is 13.5 mpg.

With a 28% to 60% error rate on the Tundra alone (depending on how one figures the difference in mileage), I question the accuracy of the remaining data.

Do you have any details on how this information was collected and how the results were calculated?
Phoenix is offline   Reply With Quote
Old 07-26-2014, 09:05 PM   #9
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
My 08 Chey 5.3 gets between 9 and 11 towing my 31 footer, depending on my speed.

At about 60 I will get better than 10.


Sent from my iPhone using Airstream Forums
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-26-2014, 09:17 PM   #10
Rivet Master
 
TinTin's Avatar
 
2009 23' FB Flying Cloud
Canmore , Alberta
Join Date: Nov 2013
Posts: 1,762
Images: 6
While the data may be somewhat disputable, the graphs are very pretty!!
__________________
Bob and Nancy
https://www.rwcphoto.smugmug.com
Cheer Up, Slow Down, Chill Out!
TinTin is offline   Reply With Quote
Old 07-26-2014, 09:44 PM   #11
Rivet Master
 
TinShack's Avatar

 
2005 28' Safari S/O
Paradise , California
Join Date: Jul 2006
Posts: 3,446
Images: 28
Quote:
Originally Posted by Phoenix View Post
Do you have any details on how this information was collected and how the results were calculated?
The references at the bottom of the chart state it was an extrapolation of a Facebook survey in which followers of Hitchanything.com were polled. Not very scientific.
__________________
Steve
"THE OLDER I GET, THE BETTER I WAS"
TinShack is offline   Reply With Quote
Old 07-26-2014, 09:54 PM   #12
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
The real answer to the question lies in the energy content of diesel v. Gasoline. Diesel has 13% more for a given volume.

This is going to be the primary factor in a logical approach to to discerning the true economy of gas v. Diesel powered trucks.


Sent from my iPhone using Airstream Forums
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-26-2014, 11:35 PM   #13
4 Rivet Member
 
Durango , Colorado
Join Date: Jan 2014
Posts: 426
You also need to take into account the re-sale of Diesel vs gas.

A diesel will have a much higher re-sale value than a similar mileage gas vehicle.

So even if better fuel economy doesn't quite make up for higher maintenance cost, re-sale might make up for the difference.

I just prefer diesel over gas because of the better performance in mountainous terrain and high altitude where most of my driving takes place.

In addition the new diesels are much better for the environment than gas.
RVDreamer is offline   Reply With Quote
Old 07-27-2014, 02:03 AM   #14
jcl
Rivet Master
 
Currently Looking...
Vancouver , British Columbia
Join Date: Oct 2012
Posts: 4,566
Quote:
Originally Posted by J. Morgan View Post
The real answer to the question lies in the energy content of diesel v. Gasoline. Diesel has 13% more for a given volume.

This is going to be the primary factor in a logical approach to to discerning the true economy of gas v. Diesel powered trucks.
If we are going to consider the volumetric energy content of the fuel as a basis for comparison, shouldn't we also use the thermal efficiency of the diesel cycle compared to the Otto cycle, referencing the compression ratio of each engine? And consider the throttling losses of an Otto cycle (gasoline) engine?

Jeff
jcl is offline   Reply With Quote
Old 07-27-2014, 08:27 AM   #15
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
InfoGraphic: Actual Fuel Economy of Diesel vs Gas Towing

We should, but i doubt there is much difference in modern gas v. Modern diesel engines.

I doubt that the difference is one percent net one way or the other.

Diesels reached the top of their game in the 90s. Since then unreasonable emission expectations have badly hurt their economy and reliability.
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-27-2014, 08:34 AM   #16
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
I think that the emission control standards of the 90s were more than clean enough for gas and diesel, and the stuff done since then is a net looser.....

But with that said,,,, I seriously doubt that modern diesel engines are easier on the environment than modern gas engines.
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-27-2014, 08:39 AM   #17
Rivet Master
 
1981 31' Excella II
New Market , Alabama
Join Date: Sep 2011
Posts: 6,145
Diesel has another economy edge other than BTU content. Diesel engines are more efficient because of the higher compression. They can extract more energy as a result of the higher compression. BTU content is not the only factor but it is a factor. The EPA putting ethanol in the gasoline does not help the BTU content of gas.

Everything on a diesel is twice as big and heavy because of the higher compression. They are also about 4 times more expensive to fix. There are also more systems to deal with especially with the new diesels. If you get a German made anything and maintenance costs will be even higher than an American made diesel. 20 yrs ago when Diesels were much simpler and diesel fuel was cheap to buy they were probably a good deal. If I want an expensive hobby, I would own a diesel. If I want to turn the key and drive with a couple hundred dollars of maintenance and year, I will drive a gasser.

Perry

Quote:
Originally Posted by J. Morgan View Post
The real answer to the question lies in the energy content of diesel v. Gasoline. Diesel has 13% more for a given volume.

This is going to be the primary factor in a logical approach to to discerning the true economy of gas v. Diesel powered trucks.


Sent from my iPhone using Airstream Forums
perryg114 is offline   Reply With Quote
Old 07-27-2014, 08:51 AM   #18
Rivet Monster
 
wahoonc's Avatar

 
1975 31' Sovereign
1980 31' Excella II
Sprung Leak , North Carolina
Join Date: Jun 2003
Posts: 7,172
Images: 40
I prefer diesel over gas for heavy hauling. I also keep a couple of old diesel trucks on the place just in case. If diesel or gas becomes unavailable or cost prohibitive I will run 100% bio diesel I did some calculations a couple of years ago, I can plant 12 acres of soybeans/rape seed or something similar and produce more than enough bio to cover my needs for a year.

Aaron
__________________
....so many Airstreams....so little time...
WBCCI #XXXX AIR #2495
Why are we in this basket...and where are we going
wahoonc is offline   Reply With Quote
Old 07-27-2014, 08:53 AM   #19
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
The compression ratio would be factored into overall efficiency. I contend that a modern gas and a modern diesel will be within one percent net in efficiency.

The engineers have worked very hard on getting the most efficiency possible out of modern engines gas and diesel alike.

Compression ratio makes less difference proportionally as it increases.
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 07-27-2014, 08:54 AM   #20
Rivet Master
 
1981 31' Excella II
New Market , Alabama
Join Date: Sep 2011
Posts: 6,145
Can you convert the stuff to biodiesel yourself though?

Perry

Quote:
Originally Posted by wahoonc View Post
I prefer diesel over gas for heavy hauling. I also keep a couple of old diesel trucks on the place just in case. If diesel or gas becomes unavailable or cost prohibitive I will run 100% bio diesel I did some calculations a couple of years ago, I can plant 12 acres of soybeans/rape seed or something similar and produce more than enough bio to cover my needs for a year.

Aaron
perryg114 is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Favorite Higher Fuel Economy Tow Vehicles ALANSD Tow Vehicles 88 07-29-2014 03:49 PM
Please list your model and fuel economy LANcamp Airstream Motorhome Forums 76 05-31-2013 12:19 PM
The Xmas fuel economy thread! Dave Park Tow Vehicles 8 12-15-2010 09:55 PM
Fuel economy loss ralley Mechanics Corner - Engines, Transmission & More... 12 01-06-2009 01:40 PM
Fuel economy ideas and MPG Boosting (merged threads) maxandgeorgia Tow Vehicles 104 07-23-2008 08:19 PM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 09:06 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.