Go Back   Thor Forums > Thor Community Forums > Thor Owners Community Discussions
Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 10-12-2017, 11:05 AM   #21
Senior Member
 
Wonderdog's Avatar
 
Brand: Thor Motor Coach
Model: Axis 25.2
State: Florida
Posts: 359
THOR #4466
Quote:
Originally Posted by Chance View Post
It comes down to simple math. Bigben's 4 MPG guess isn't unrealistic at all. If anything it's too high for large motorhomes going up steep grades.

Any gasoline engine will need to burn approximately 20 gallons per hour of fuel to make 300 HP; more or less -- engines vary just a little.

So whether you have a V10, Hemi, 5.0 V8 or EcoBoost for that matter, if your rig is large enough to only go uphill at say 40 MPH while using 300 HP, you'll be getting +/- 2 MPG.


(40 miles/hour) / (20 gallons/hour) = 2 miles/gallon.

I'm sure than on really steep hills like we have in Texas, some large rigs may only get about 1 MPG while climbing at 20 MPH or so.
Which of course means that no, you didn't just imagine it, you really could see the gas gauge drop when you put your foot in it.
__________________

__________________
---------------
Dennis and Pam
2017 Axis 25.2
Toad - 2004 Honda CR-V
Wonderdog is offline   Reply With Quote
Old 10-12-2017, 11:44 AM   #22
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 4,698
THOR #2121
Quote:
Originally Posted by Wonderdog View Post
Which of course means that no, you didn't just imagine it, you really could see the gas gauge drop when you put your foot in it.

Absolutely. But it's not because the V10 is inefficient like we keep hearing. To make lots of power it takes lots of fuel, no matter what engine you have.

When Ford comes out with a new and more powerful replacement for the V10 in the next couple of years, it may be slightly more efficient, but if it makes a lot more power (say 400 HP or more), it will be able to burn fuel even faster.

Simple reverse engineering suggests that when a motorhome is getting 7 MPG at 70 MPH (hence burning average of 10 gallons per hour), the engine is making about 150 HP.

A newer engine may be 5 or 10 percent more efficient, but fuel economy is still going to suck unless load on engine is reduced a lot. Bottom line: don't blame V10 for poor MPG. Blame the coach.
__________________

__________________
Chance is offline   Reply With Quote
Old 10-12-2017, 12:01 PM   #23
I Think We're Lost!
 
Bob Denman's Avatar
 
Brand: Still Looking
Model: Tiffin Wayfarer 24 BW
State: New York
Posts: 16,274
THOR #8860
Sooooo.... Who bought their RV for the fuel economy??
__________________
Good Sam Member 843599689
Current coach: Tiffin Wayfarer 24 BW
"History shows again and again; how Nature points out the folly of Man!"
Bob Denman is offline   Reply With Quote
Old 10-12-2017, 12:09 PM   #24
Senior Member
 
bigben's Avatar
 
Brand: Thor Motor Coach
Model: Challenger 37TB
State: Kentucky
Posts: 1,032
THOR #1020
Talking Yepper

Quote:
Originally Posted by Bob Denman View Post
Sooooo.... Who bought their RV for the fuel economy??
I know we did!
__________________
US Army Retired - Loving The Road Trip
Challenger 37TB
bigben is offline   Reply With Quote
Old 10-12-2017, 12:17 PM   #25
I Think We're Lost!
 
Bob Denman's Avatar
 
Brand: Still Looking
Model: Tiffin Wayfarer 24 BW
State: New York
Posts: 16,274
THOR #8860
How's that working out for you?
Are you getting mileage numbers that are high enough, to use the rig as your "Toad"; when you take the Smart Car out for a spin on the highway??
__________________
Good Sam Member 843599689
Current coach: Tiffin Wayfarer 24 BW
"History shows again and again; how Nature points out the folly of Man!"
Bob Denman is offline   Reply With Quote
Old 10-12-2017, 01:00 PM   #26
Senior Member
 
bigben's Avatar
 
Brand: Thor Motor Coach
Model: Challenger 37TB
State: Kentucky
Posts: 1,032
THOR #1020
Too Funny!!
__________________
US Army Retired - Loving The Road Trip
Challenger 37TB
bigben is offline   Reply With Quote
Old 10-12-2017, 01:17 PM   #27
Senior Member
 
Brand: Still Looking
State: Texas
Posts: 4,698
THOR #2121
Quote:
Originally Posted by Bob Denman View Post
Sooooo.... Who bought their RV for the fuel economy??

If you mostly leave it parked in driveway, I guess it really doesn't matter much, does it?

Add up fuel cost for 175,000 miles and you start to see a slightly different picture.

Depends how you plan to use it. In my case yes, fuel economy matters. I previously did not like owning a motorhome that got used mostly for traveling that only got 8 MPG, so I got rid of it. It felt wasteful.
__________________
Chance is offline   Reply With Quote
Old 10-12-2017, 01:56 PM   #28
Senior Member
 
bigben's Avatar
 
Brand: Thor Motor Coach
Model: Challenger 37TB
State: Kentucky
Posts: 1,032
THOR #1020
As I indicated, it is all about choices. We wanted a coach big enough to travel with our grandkids (3-5 most times) and still be comfortable. With our 37TB we can easily sleep up to 5 of them, with a bath and half, a king size bed for us, plenty of storage underneath and the ability to tow our 7 passenger Explorer. Does the gas mileage hurt, yep. We've taken 3 major trips for the last 3 years summer vacations with grandkids. They have traveled through 30+ states of our USA, visiting Old Faithful, sleeping in the redwood forests, riding a train to the Grand Canyon, eating lobster in Bar Harbor, visiting NYC Great White Way, carriage ride in Central Park, on and on and on. And we snowbird in warmer climates each winter living in our coach - often dry camping for 3 months at a time. Based on our choices it wasn't wasteful. So it is truly is about choices.
__________________
US Army Retired - Loving The Road Trip
Challenger 37TB
bigben is offline   Reply With Quote
Old 10-12-2017, 02:16 PM   #29
I Think We're Lost!
 
Bob Denman's Avatar
 
Brand: Still Looking
Model: Tiffin Wayfarer 24 BW
State: New York
Posts: 16,274
THOR #8860
Quote:
Originally Posted by Chance View Post
If you mostly leave it parked in driveway, I guess it really doesn't matter much, does it?

Add up fuel cost for 175,000 miles and you start to see a slightly different picture.

Depends how you plan to use it. In my case yes, fuel economy matters. I previously did not like owning a motorhome that got used mostly for traveling that only got 8 MPG, so I got rid of it. It felt wasteful.
I'm happy to agree that the dollars can add up...
How many years, does it take you, to reach that 175,000 mile mark?
How is the fuel economy on your new rig?
__________________
Good Sam Member 843599689
Current coach: Tiffin Wayfarer 24 BW
"History shows again and again; how Nature points out the folly of Man!"
Bob Denman is offline   Reply With Quote
Old 10-12-2017, 05:09 PM   #30
Senior Member
 
Brand: Thor Motor Coach
Model: Windsport 27K
State: Kentucky
Posts: 740
THOR #2817
I have a 2015 K27 Windsport. Normally I pull a 12 foot dual axle trailer with a heavy tool box, a large motorcycle, and at least a couple hundred pounds of other stuff. I have kept track of fuel mileage over the past 15,000 miles and it it about 7.5 mpg with a high of just over 10 mpg and a low of 4.3 mpg. The large variation probably has to do with the amount of fuel put in the tank at fill-ups (sometimes it might get filled more than other times.), terrain, and wind speed and direction. However, there is one more variable. How much has the generator been used between fill-ups? I keep track of the hours of use between fill ups and it can vary from zero to almost ten hours. Several hours of use will negatively affect fuel mileage in a big way.
__________________
Metalman is offline   Reply With Quote
Old 10-12-2017, 05:53 PM   #31
I Think We're Lost!
 
Bob Denman's Avatar
 
Brand: Still Looking
Model: Tiffin Wayfarer 24 BW
State: New York
Posts: 16,274
THOR #8860
I've wondered about how much the generator affects the fuel usage...
It might make life more comfortable; but it sure doesn't get us down the road any further!
__________________
Good Sam Member 843599689
Current coach: Tiffin Wayfarer 24 BW
"History shows again and again; how Nature points out the folly of Man!"
Bob Denman is offline   Reply With Quote
Old 10-12-2017, 07:40 PM   #32
Senior Member
 
bigben's Avatar
 
Brand: Thor Motor Coach
Model: Challenger 37TB
State: Kentucky
Posts: 1,032
THOR #1020
Support manuals for our 5.5 KW Onan say at minimum load it uses .6 gals per hour. So yep, if you run the gennie for 5 hours while moving down the road you've used 3 gallons. Again, it is about choices. When traveling in 85-90 degree heat with 3 grandkids in the rear without the 110 AC on I'll hear "Pappaw - we're hot and sticky!". Easy call.
__________________
US Army Retired - Loving The Road Trip
Challenger 37TB
bigben is offline   Reply With Quote
Old 10-12-2017, 08:06 PM   #33
Senior Member
 
Whirnot's Avatar
 
Brand: Thor Motor Coach
Model: Vegas 25.2
State: Oregon
Posts: 271
THOR #6934
Quote:
Originally Posted by Mr Sunshine View Post
No one has mentioned the obvious: higher highway speeds=lower mpg.

"Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?" - George Carlin
"I don't car who you are, that's funny" - Larry the Cable Guy
__________________
Whirnot is offline   Reply With Quote
Old 10-12-2017, 10:01 PM   #34
I Think We're Lost!
 
Bob Denman's Avatar
 
Brand: Still Looking
Model: Tiffin Wayfarer 24 BW
State: New York
Posts: 16,274
THOR #8860
Someone else also said it...

__________________

__________________
Good Sam Member 843599689
Current coach: Tiffin Wayfarer 24 BW
"History shows again and again; how Nature points out the folly of Man!"
Bob Denman is offline   Reply With Quote
Reply

Thread Tools
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


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Thor Industries or any of its affiliates. This is an independent, unofficial site.




All times are GMT. The time now is 08:03 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0 PL2
×