Improving Gas Mileage

JerJ · 03-28-2016, 05:55 PM

My wife and I did our shake down trip this past Easter weekend in our new 2016 Forester 3011 DS. Even though it rained the entire weekend, we had an enjoyable trip. Driving the RV in bad weather was much easier than I thought it would be, It was also a good opportunity to look for possible leaks. Happy to report there weren't any.
The gas mileage wasn't very good, but I expected that. On this trip we got about 8.3 MPG. I was wondering if anyone with a similar RV, Ford E 450, has installed a K&N high performance air filter and a Programmer? If yes, is there a noticeable improvement in power and gas mileage? Any suggestions on how to improve the gas mileage would also be appreciated. On this trip we were not towing a car, Also, since it was just a weekend trip we were not carrying a lot on board.
Thank you.

jrwalkerpa1 · 03-28-2016, 06:32 PM

Well, I have good news and bad news.....the good news is 8.3 is a good average mpg for a brand new unit. The bad news is...that's about as good as it's going to get...

We've looked into many options both in this unit and past units. We had a banks system in an older class c that did increase power but nothing really increases fuel economy beyond anything that is statistically significant....

We have the sunseeker twin to your unit...3010ds and we are pleased to average over 8. Sometimes if the conditions are right and we keep the speed at 55 or under we get as much as 9-10 but that is rare. If you can average between 8 and 9, you're doing good!

Wandering · 03-28-2016, 08:10 PM

I've got a smaller unit and struggle to get 8 MPH. Look forward to more ideas on better mileage.

Congrats on new unit & Happy Camping

Forester 2451s

wanderingbob · 03-28-2016, 08:23 PM

Slow down , I get 25% better at 60 MPH as at 70 MPH.

sgtlm17 · 03-28-2016, 08:24 PM

I averaged around 9mpg on way home from picking my v10 up. Ford new 6 speed drove solid with great shifting and just gobs of power. Extremely pleased. Drove 600 miles.

2016 Forester GTS 2801QSF

acadianbob · 03-28-2016, 08:35 PM

A tune is not going to improve your mileage. Slowing down is the best way to do that.

Bluepill · 03-28-2016, 08:35 PM

Yes, sadly, slowing down is the best way. We got stuck in Cal. on a road that was posted at 55 mph for trucks and vehicles towing, vs. 70 for cars. Besides the insanity of having a 15 MPH differential between adjacent lanes (What were they smoking when they thought that one up?), it did kick our MPG from about 8.8 to 10.

Wind drag goes up as the square of speed. It's the law.

LTRVing · 03-28-2016, 09:28 PM

I have a 2013 SS 3170DS, with E450, @67 mph we got 7.5 mpg, slowing down to 60 got us almost 9 mpg. Plus, I felt much more in control at 60-62 mph.

Creativepart · 03-29-2016, 12:28 AM

We just returned from a 800 mile trip last week. The wind was horrible and we averaged 6.7 mpg. On the return the wind was still bad but better and we averaged 7.5 mpg. We're happy to get 8.0 and celebrate when we see 8.5. So if you got 8.5 out of the box you're doing good.

I do tend to drive 65 most of the time.

HappyGuy · 03-29-2016, 07:28 AM

Best I ever got was 9.2 mpg unloaded and averaging 65 mph on the way up to Indiana for some warranty work. Loaded I get mid 8s fairly regularly averaging between 60 and 65 mph and with a toad out back I will see anywhere between 7.6 and 8.2 at the same speeds. My old C was almost 10 feet shorter and more than a ton lighter than my 3011 with the same engine and transmission. It got very similar mileage numbers at the same speeds. You're driving a box and all that wind pushing against it is going to be the main drag on your mpg (pun intended).

radman · 03-29-2016, 12:01 PM

I have had 2 Class Cs, both with the V-10. The best mileage I ever recorded was about 10.5 to almost 11 mpg, but I was on a 2 lane road going about 50. My new 3051 I am getting about 8.5 going 65. The only way that I know to increase mpg is just to keep it about 60, but that is hard to do on the Interstates.

Gidyupgo · 03-29-2016, 04:50 PM

Dragging a parachute. Thats how I've heard the drag from the square tail on a RV described. Same article said the extra weight of a reasonably sized Toad is offset by the reduced drag because the Toad breaks the parachute. Dunno if it's true.

A32Deuce · 03-29-2016, 05:00 PM

I tow a open car trailer/with Falcon every where and depending on speed, weather, traffic and terrain will average between 7.5 and 9.5. Cold air intake and Banks controller for trans shifting.

GigSeeker · 05-16-2018, 11:43 AM

Quote:

Originally Posted by HappyGuy

Best I ever got was 9.2 mpg unloaded and averaging 65 mph on the way up to Indiana for some warranty work. Loaded I get mid 8s fairly regularly averaging between 60 and 65 mph and with a toad out back I will see anywhere between 7.6 and 8.2 at the same speeds. My old C was almost 10 feet shorter and more than a ton lighter than my 3011 with the same engine and transmission. It got very similar mileage numbers at the same speeds. You're driving a box and all that wind pushing against it is going to be the main drag on your mpg (pun intended).

We just drove 800 miles in our 2500TS and got 8.3. Speeds between 55-65. Some crosswind. 30 gals of water. Up and some hills. I found it better to drive at night, less wind, less drivers that don't know how to accelerate the on ramps. Less air conditioning demand. I wondered if rear farings like trailer tails would reduce drag. As it is we are hit on both ends, front pushing air aside and the rear being sucked rearward by the vacuum created. Can't help the front. The rear, maybe.

Gidyupgo · 05-17-2018, 09:38 PM

GigSeeker, I remember reading somewhere that the toad breaks up the suction effect.

Viatorem · 10-01-2018, 12:22 AM

I too have the new f53 with v-10, towing a 2dr Jeep Wrangler. Got fuel after burning 1/2 tank cruising at 65mph (2500rpm) and did the math. My jaw hit the floor and I checked the math... 6mpg! This last trip was same configuration, less wind, kept speed at 60 or less and got 7mpg. I don’t expect to ever see 10mpg..unless no toad and I cruise at 45mph. Lol.

Duckogram · 10-01-2018, 07:55 AM

Quote:

Originally Posted by Viatorem

I too have the new f53 with v-10, towing a 2dr Jeep Wrangler. Got fuel after burning 1/2 tank cruising at 65mph (2500rpm) and did the math. My jaw hit the floor and I checked the math... 6mpg! This last trip was same configuration, less wind, kept speed at 60 or less and got 7mpg. I don’t expect to ever see 10mpg..unless no toad and I cruise at 45mph. Lol.

Not “too”. Foresters are E-450’s, Mercedes Benz Sprinters or Ford Transits.
No big box F-53’s. I get a touch over 9 average with a well balanced GTS towing a Fortwo at about 60 mph on 87 octane. I use a 5 Star Custom tune.
My big box with the 5 Star towing the same car at the same speed got an average of 7.5.

For the OP: A trailer tail might help if you have no rear slide. Vortex generators that stick on the edge have been shown to be ineffective. Reducing weight and mass will have an effect but I’ve been told that leaving my spouse home will not work.

Chuck_S · 10-01-2018, 08:28 AM

Want to save fuel? Slow down.

Once rolling air resistance is the primary consumer of power and air resistance increases exponentially with speed. Fuel use is directly related to power needed. The air resistance of any object at 70 mph is twice what it was at 50 mph.

Air resistance can be reduced by engineering, the Prius being a prime example, but pushing our aerodynamic bricks thru the air is very inefficient.

-- Chuck

Total Loss · 10-01-2018, 09:25 AM

Chevy 6.0 with a 6 spd. 60-65 mph averages.
I got 11 on my last 3200 mile trip with 500 lbs on the rear (no toad).
I have a GVW of about 11,500 loaded.
With my 4000 lb toad I get about 9.5.

2 less cylinders than the V10 and shifting manually.
I probably would not want the 6.0 with any larger box though.
Works perfect as is.

Key here as everyone stated...slow down. 60-65 is much more comfortable and easier on the wallet.

Chuck_S · 10-01-2018, 10:04 AM

Speed does not always save time if there is any distance involved.

When my daughter (and my money) went to Gettysburg College my drive at "plus 10" from Cleveland across the mountains on the turnpikes required a fuel stop with my Expedition. At the speed limit I could get there with no fuel stop. Times were identical. The delay caused by getting off the road and refueling negated the benefit of the faster speed. And burning less fuel saved (probably) enough money to buy a beer when I got there.

Towing the camper, of course, burns a lot more fuel.

-- Chuck

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