HI Guys, I like these posts which go on for years... Towing with my Dodge at 60 mph gets 13 mpg. At 70 mph gets 11 mpg. Secondary roads at 55 mph... about 12.5 mpg, most likely due to start/stop driving as towns come up frequently in the Eastern US.
Interestingly enough at 60 mph in 70 zones I seem to be passed by the same people over and over. I stop every 250 - 350 miles for fuel or whatever. They must be stopping for ???
At 60 I seem to be quite relaxed and can tow for 700 miles in a day.... That is about 14 hours total time from start to finish. Includes a relaxing lunch, etc.
A few years ago I towed a motorcycle trailer to California, 5000 miles round trip, with a Porsche Cayenne Turbo. The most fun was going through the Rockies, up the side of the mountains at 80 mph, passing all the other cars breathing heavily. I am older and slower now... not wiser, just slower.... Safe travels
__________________ Msmoto aka Ms Tommie Fantine Lauer, MD, FASAM
High Point, NC
'09 27FB International Ocean Breeze behind an '08 Dodge QuadCab LongBed 4x4 Cummins Diesel / WBCCI 4156 / Friend of Bill Wilson
...maybe a place to park?
63-65 MPH is the magic point between 15 MPG and 11 MPG in our '97 F250 diesel. Only exception to the rule was in North texas in June of '07 we where watching a storm cell off to the east of us that was getting bigger.
And Biggerm, it might have had a little swirly motion to it.
I was pretty calm about it untill we got passed by a big ol' Class A diesel pusher that was blowing smoke like uncle Lew's cigar. After a quick calculation on what he was spending per second in diesel, I decided he might know something about that storm cell that I didnt and decided it was time to punch it on out of there.
You dont worry about throwing a hub, or shredding a tire when pulling a 20' Avion at 90 miles an hour because the wheels dont touch the ground.
....apears I got side tracked again.
__________________
Champagne wishes and Caviar dreams!
Budwieser budget.
Wow... I'm starting to feel like an old fart... never mind that I AM an old fart. You guys (and gals) towing at 70 or greater scare the beejezus out of me. We drove home from Denali Park this weekend and had some fellow pass us like a bat out of heck in a little Chevy SUV towing a SOB. He had to have been doing all of 80. We blinked a couple of times and he was out of sight, wobbling all over the road. We rarely break 58 towing out little 25'... It tows like a dream but I just have no desire to push my luck should something (or someone) happen... and I'm happy with the 15+ MPG we get at that speed.
Depending on conditions and traffic 60-70. My - 7.3L f350 gets best MPG in that range too - approx 14-15 mpg. Powerful side wind quickly gets me below 60 for safety.
You guys (and gals) towing at 70 or greater scare the beejezus out of me.
Granted, if someone is driving like you described, it would scare me too, but if someone isn't swerving all over the place, I don't get it. I drive the posted speed limit on the interstate and off. On the interstate I might go 5 MPH more, but if you are scared by life, stay at home. I'm more afraid of truckers driving 80+ with 40K lbs behind them than I am a 3/4 ton truck/SUV with 10K (or less) behind it. At least most RV'ers aren't pushing their limits against fatigue, lack of sleep, or in the rare occasion on speed to make it to their next stop before the boss chews his _ _ _ out.
__________________
2006 30' Safari - "Changes in Latitudes"
2008 F-250 Lariat Power Stroke Diesel Crew Cab SWB
Family of Disney Fanatics
WBCCI# 4821 streamin across america
Not scared of life... I would just prefer to keep on living it. Someone (or something) pulls out in front of you, sudden stops, tire blowouts, etc. would all be bad enough at 55ish but the farther the speedo is leaning to the right, the worse it could potentially be. I'm not admonishing anyone... just sayin'... and it goes for RV'ers, truckers and frankly anyone who pushes the safety envelope where I, my wife, kids and grandkids could get caught in the crosshairs.
I pull at 60 - 65 most of the time and get around 12 - 15 MPG with my 2007 F250SD Diesel depending on wind conditions. Pushing up to 70 will drop mileage to 10.5 - 12 MPG. I have concern about the tires coming apart at too high a speed and doing a lot of damage to the AS. The tires are still like new even though my AS is 4 years old and has been towed only about 3000 miles but is stored in an enclosed garage. Also slowing down a little seems to make trips much more relaxing. After all who needs to be in a hurry when retired or on vacation?
I'm certainly not saying that anyone should tow, or drive, any faster than they feel comfortable. But, if you keep your tow vehicle and your Airstream properly maintained and your trailer's tires inflated to 65 PSI, you shouldn't have any problems with interstate speeds.
BTW, driving slow being relaxing is relative. Too long behind the wheel and I get antsy and impatient to get there.
__________________
2006 30' Safari - "Changes in Latitudes"
2008 F-250 Lariat Power Stroke Diesel Crew Cab SWB
Family of Disney Fanatics
WBCCI# 4821 streamin across america
Wow, these things seem to change. I just returned from a New Orleans/Houston pull and did some speed testing. I noticed when I used the exhaust brake this tended to decrease fuel mileage. If I traveled on the back roads at 55 mph with the start/stop of city traffic, fuel mileage was less than 60 mph on Interstate Highways. In my 2008 Dodge Cummins Diesel 2500 61 mph was clearly better than 62 mph. I think this has to do with the cruise and on some very steep rolling country roads a downshift would occur if I did not pay attention. Ultimately, I found my mileage has now improved to about 14.7 mpg at 61 mpg on three consecutive tanks. I bought the truck in October 2008 and the engine has 18,000 miles on it and is almost broken in. My schedule for 2009 is another 12,000 miles of pulling around the country. I am planning on full documentation of mpg in order to learn more.
Incidentally, the Bayou Segnette State Park in New Orleans is very nice and if one drives down to the Algiers Ferry and rides free across to the French Quarter one sees a totally different New Orleans. Parking in Algiers is $5 - 10 as opposed to $30 in the city.
__________________ Msmoto aka Ms Tommie Fantine Lauer, MD, FASAM
High Point, NC
'09 27FB International Ocean Breeze behind an '08 Dodge QuadCab LongBed 4x4 Cummins Diesel / WBCCI 4156 / Friend of Bill Wilson
...maybe a place to park?
I have tried different speeds and 5 MPH has 0 affect on my fuel consumption. That's using the tow command and cruise control on fairly level terrain.
__________________
2006 30' Safari - "Changes in Latitudes"
2008 F-250 Lariat Power Stroke Diesel Crew Cab SWB
Family of Disney Fanatics
WBCCI# 4821 streamin across america
I have tried different speeds and 5 MPH has 0 affect on my fuel consumption. That's using the tow command and cruise control on fairly level terrain.
On the way to Montana. last year, I tried 55 and then 60. I had measurably better results at 60, mainly because it brought the RPMs up to where the diesel was happier. There were noticeably fewer shifts out of 6th gear at 60 vs 55.
My usual cruising speed is 62-63 MPH. That is where the diesel (Duramax) seems happiest and downshifts are very few unless the terrain is quite hilly.
__________________
John W. Irwin
2005 Classic 28 "Sabre-Dog III"
2007 Silverado 2500HD Duramax/Allison LTZ
WBCCI Region 9 Webmaster, #9632
At 55 I'm still in the 5th gear. I don't get into the overdrive (6th gear) until I'm over 65. The RPM's at 75 are the same as at 55. They aren't noticeably lower at 70. At around 68 is where they drop. At 70, the transmission tends to search for the right gear going uphill sometimes. I have to use the cruise on interstates to keep from creaping up to 80 if not paying strict attention to the speedometer.
__________________
2006 30' Safari - "Changes in Latitudes"
2008 F-250 Lariat Power Stroke Diesel Crew Cab SWB
Family of Disney Fanatics
WBCCI# 4821 streamin across america
At 55 I'm still in the 5th gear. I don't get into the overdrive (6th gear) until I'm over 65.
The Allison 6-speed is a double overdrive transmission. 5th gear is the same as 5th was in the former 5-speed in my 2003.
With the Classic 28 in tow, I can be in 6th from the mid-50s up. At the lower speeds, I am more likely to drop to 5th on a mild hill. At over 60, it takes a considerable rise to force a shift down out of 6th. Some unintended downshifts occur when I am running in cruise control and encounter a sudden rise.
I like to run in manual shift in Cruise. If I see a rise coming, I touch the downshift button as soon as I hear the engine loading up. That bumps me down to 5th. As I near the top of the hill, I touch the upshift button. Nothing happens instantly, but as the load comes off the engine, a shift back into 6th will occur. This mode of operation gives me the best fuel mileage abnd I never have to touch the accelerator..
__________________
John W. Irwin
2005 Classic 28 "Sabre-Dog III"
2007 Silverado 2500HD Duramax/Allison LTZ
WBCCI Region 9 Webmaster, #9632