Flat towing and gas milage.

[CrowCross]

Hi Folks,
I have a 2016 Jayco 31 DS Greyhawk with a Ford E 450 Super Duty motor.

Been across country twice and got about 7.5 to 8 MPG.

We're thinking about flat towing a vehicle and was wondering what it does to the gas milage.

Also, what speed do you tow at and what kind of car are you pulling.

Karl

[Grumpy]

When we had our 01 the difference wasn't even noticeable. We averaged 7.5 as well. The big factor in mileage is wind resistance and with it behind the MH that is minimal. I stayed between 62-65 and towed both an S-10 and a GMC Canyon 4wd.

[RPR]

We have a 2018 31DS and tow a Nissan Altima on a tow dolly. 8mpg drive 65 mph max.

[tom463219]

Average 7 -8 MPG towing 4000 lb 2016 Chev Equinox

Mostly run US Routes, avoiding Interstates when I can.

[Bullitt6283]

I run 60-65 MPH.
I cannot really tell if there's much difference in MPG....


.

[Foretm]

We average around 7.5 mpg and run about 65 mph. Toad is a Saturn Astra 2880lbs.

[Love To Travel 2]

We flat tow a 2018 Chevy Equinox behind our 2018 29MV. We very seldom drive without the toad, so I can't really say what the average MPG is without the Equinox. When I would accurately check the mileage on long trips with the Equinox attached, I would see 8 to 8.5 MPG, but I think 8 is closer to the norm. As far as speed, 60 to 65 is my limit. If they want to pass me on the 70 MPH highways, I let them. Since 250-275 miles per day is my limit, I'm not in any hurry to get there.

[Harvard]

Originally Posted by Bullitt6283

I run 60-65 MPH.
I cannot really tell if there's much difference in MPG....
.

Your post has a perfect panoramic view of your RV. From this picture I am estimating that your RV has a nose up attitude of about 1/2 degree from horizontal. The horizontal reference being from the top of the front wheel rim to the top of the aft wheel rim.

Further more, from my theory of how these RVs are "as built" I am guestimating this unit came off the RV build with a caster of about +5.0 degrees. So, have you ever had cause to have this unit aligned? Have you ever had any handling issues such as wandering at highway speeds?

The context of this inquiry, the theory being:

Ford ships all E350/E450 cut aways with identical fixed, non adjustable
caster/camber sleeves, "one size fits all".

The RV builder almost never changes the Ford sleeves, as a result:

If the final RV build is nose down one degree then the runtime caster will be about +3.5 degrees. These units can have a real wandering problem.

If the final RV build is nose level then the runtime caster will be about +4.5 degrees. These units are probably indifferent.

If the final RV build is nose up one degree then the runtime caster will be about +5.5 degrees. These units are probably just fine.

So, some RVs have a problem and some do not have a problem.

POPULAR MECHANICS MAY 1973:
START QUOTE:
If too little caster exists, the car will wander and weave,
thus necessitating constant corrections in steering.
END QUOTE:

[Davidmac]

Our 2016 Grayhawk 29mv towing a 2012 Honda CRV consistently gets 7.5 MPG . We travel the east coast from Florida to Canada not exceeding 65 MPH . We have always towed a vehicle .

[Bullitt6283]

Originally Posted by Bullitt6283

I run 60-65 MPH.
I cannot really tell if there's much difference in MPG....

Originally Posted by Harvard

Your post has a perfect panoramic view of your RV. From this picture I am estimating that your RV has a nose up attitude of about 1/2 degree from horizontal. The horizontal reference being from the top of the front wheel rim to the top of the aft wheel rim.
Further more, from my theory of how these RVs are "as built" I am guestimating this unit came off the RV build with a caster of about +5.0 degrees. So, have you ever had cause to have this unit aligned? Have you ever had any handling issues such as wandering at highway speeds?

Originally, there was a large amount of 'wander' driving down the road. It was definitely not fun driving.

I had the front end aligned at a truck shop who is familiar with working on RVs. The shop installed adjustable sleeves to adjust the caster. I don't have record of the final caster degree amount, but there was a definite improvement. The shop owner commented that it was good I had it fixed early. He said that usually he sees RVs after the front tires are worn.

Later, I installed the Safe-T-Plus stabilizer. More improvement was seen.

Then I removed the stock Econoline front sway bar and installed the Helwig front bar. Truthfully, I could not tell much difference.

Driving is now much better. Passing trucks are still noticed, but control is vastly better.

[jd99336]

31 DS towing a 2016 Jeep Cherokee Trailhawk. 7 to 7.5, but in some cases down into the 6's. We are in Washington and the towing is a lot of hills, and two lane black top. I too keep the speed at 60-65 usually settling around 62. I use the GPS for speed determination as the speed registers fast by about 3 mph.

[Jicama]

2019 Redhawk flat towing a 2010 Kia rio5 not exceeding 70 mph. No issues at all 7.5-8mpg

[greyhawktom]

31 fk tow a ford ranger 60-63 mph, mostly 7.5 mpg

[Crossingover]

Diesel experience here, but should provide relevant insight into the expected deltas: 62 mph flatland towing a stock-wheeled Jeep Wrangler JKU averages upper-8's mpg; without a toad, upper 9's/low 10's mpg. Throw big head/tail winds into the scenario and these numbers change considerably.