Reply
 
Thread Tools Display Modes
Old 05-27-2011, 11:05 AM   #1
Junior Member
 
DBlum's Avatar
 
Join Date: May 2011
Location: Northern Ca.
Posts: 8
Question Diesel MPG

We are currently towing a superlite Flagstaff 5th wheel (Tow weight at 8700 lbs) with a Ford 150 (maximum tow rating at 9800 lbs) that has inadequate brakes to handle serious downhill grades (with TH and TBC). We are considering purchasing a 250/2500 diesel and are wondering what the real world is achieving in MPG while towing and when used in regular driving.
__________________

__________________
DBlum is offline   Reply With Quote
Old 05-27-2011, 12:12 PM   #2
Senior Member
 
Nigels's Avatar
 
Join Date: Jul 2010
Location: BC Canada
Posts: 632
We bought our 2011, 3500 4x4 Cummins Ram Auto (stock) 6 weeks ago and have done almost 14000kms in it, over half that towing and here's our results, 90% of the time using cruise, except towing on up grades I switch off cruise.

Without 5th wheel:
55-60mph open road 19-21mpg
Urban 14-17mpg

Towing 5er +- 8500lbs:
55-60mph open road 11-13mpg
With head wind 55-60mph open road 9mpg

We have crossed the rockies and done some steep and twisties both with and without the 5th wheel and the mpg difference is almost nothing maybee half a gallon worse.

On all the decents we used the engine brake, barely if ever did we use the normal brakes.
__________________

__________________
Nigel & Bev
Brit Driver & Canadian Naviguesser

2011 Rockwood Signature Ultra Lite 8280ws
2011 Dodge Ram 3500 4x4 Diesel
http://www.algarvevillaforrent.com
Nigels is offline   Reply With Quote
Old 05-27-2011, 01:02 PM   #3
Senior Member
 
onetonford's Avatar
 
Join Date: Oct 2010
Posts: 627
With mine towing trailer home from RV dealer best was 14.5 worst 13 that is 8750 lbs trailer 9580 truck. Truck alone was 20 best worse 13.
Old fiver which was only 4000 lbs best 14 worst 13. It had a very flat nose and the wind would kill the fuel mileage. New fiver must be more aero dynamic than old unit of course will see week after next going for a long drive with it and mostly south down
I-5 which is like a wind tunnel that way.
__________________

2001 Ford F-350 DRW 7.3
2011 25 RL Wildcat
former fiver 1976 Fourwinds had for 35 years
onetonford is offline   Reply With Quote
Old 05-27-2011, 02:59 PM   #4
Member
 
Join Date: Oct 2010
Posts: 34
With my 2011 2500 Silverado/Duramax/Allison I average about 12 mpg towing. Running empty on open roads or interstate 18-22, but just putting around home (stop & go) I'd say about 15 mpg. For a truck that will pull anything I want to hook behind it.....I'm satisfied.
__________________

2007 Rockwood Signature Ultra Lite 8280SS
2011 Silverado 2500HD/ Duramax 6.6/ Allison
smilin joe is offline   Reply With Quote
Old 05-27-2011, 03:24 PM   #5
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 21,168
Used to get 13 towing my Flagstaff 8526RLWS 5th wheel at 9100 pounds.
Then I put the bikes on the front of the truck and got 12 on average.

Bikes are now in the shed and I should see the MPG back where it was.

Head Wind in addition to speed is an MPG killer. Best MPG is achieved (for me) at 55 MPH no wind. At 55 I have hit 14 MPG - But I never drive here even if the limit is 55. You will get run over by near everyone.

At 60 - 13.0 MPG
At 65 MPH it drops to 12.0
At 70 it is 11.

Take 1 MPG off if the bikes are on.

Oh, and Ditto - LOVE my truck!
__________________

Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW
Herk7769 is offline   Reply With Quote
Old 05-27-2011, 03:25 PM   #6
Senior Member
 
kz08h5's Avatar
 
Join Date: Apr 2009
Location: Carmel, Indiana
Posts: 308
I just got a '08 Silverado 2500 Duramax. The first outing was this past weekend. I getting a little over 13 mpg while driving 65mph or less. It drops to 10.5 while driving 70 to 75 mph. The TT and TV total gross weight was 13900 lbs per the scale I used at a truck stop. TT should weigh in at about 6700 lbs. I can get 17 to 18 mpg on the interstates with no trailer.

Just to show how aerodynamics affect things. I pulled a car on a U-Haul trailer that totaled 6100 lbs. The roof of the car was about even with the top of the truck bed. I averaged 15.5 mpg between Dallas Texas and Indianapolis, Ind. I tried to keep the speed at 65 mph or below but would find myself hitting 70 to 75 mph.
__________________
kz08h5

2008 Chevy Silverado 2500 Duramax Crewcab
Jeep Commander - sold
Flagstaff V-Lite WRB26
kz08h5 is offline   Reply With Quote
Old 05-27-2011, 04:16 PM   #7
Senior Member
 
Nigels's Avatar
 
Join Date: Jul 2010
Location: BC Canada
Posts: 632
Obviously head winds and wind resistance is a huge factor in MPGs, I have seen the odd deflector sitting atop a truck but IMO they just don't look right to me, and the hassle of putting it on and off, up or down, do they really work? Even if they did I think I would prefer to pay for the extra diesel.

I put a rear diffuser on my S2000 and I gained about 1.5 seconds on our local track, how about a diffuser on the 5er
__________________
Nigel & Bev
Brit Driver & Canadian Naviguesser

2011 Rockwood Signature Ultra Lite 8280ws
2011 Dodge Ram 3500 4x4 Diesel
http://www.algarvevillaforrent.com
Nigels is offline   Reply With Quote
Old 05-27-2011, 04:25 PM   #8
Senior Member
 
onetonford's Avatar
 
Join Date: Oct 2010
Posts: 627
Used to tow the old fiver with a 1977 F150 w/400 cid v8 was only rated for 185hp and that would only get 12 mpg no matter what that is what it got towing or not I used to call it my gutless wonder or four square engine. 4inch bore 4inch stroke.
It actually did pretty good any hill you would drop to 45mph and second gear. But it lasted for 165,000 miles before I sold it.
__________________

2001 Ford F-350 DRW 7.3
2011 25 RL Wildcat
former fiver 1976 Fourwinds had for 35 years
onetonford is offline   Reply With Quote
Old 05-27-2011, 07:32 PM   #9
Member
 
Join Date: May 2011
Posts: 66
2009 F-250 diesel with a 33' 5er (silverback). CAT scale shows the trailer to weight about 12,000 loaded.

Only at 23k miles on the truck - getting 17-18 commuting to work, 12-13 pulling the 5er. I have noticed the mileage getting slightly better as the engine breaks in.
__________________
kablair is offline   Reply With Quote
Old 05-27-2011, 08:51 PM   #10
Senior Member
 
Join Date: Jan 2011
Location: Ennis TX
Posts: 245
06 f350 about 14-15 pulling 8500 lb wildwood. Running 17-18 empty.

Daniel
__________________

__________________
firedaniel 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



» Virginia Campgrounds

Reviews provided by




ForestRiverForums.com is not in any way associated with Forest River, Inc. or its associated RV manufacturing divisions.


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 10:26 AM.