15 MPG Pulling a FC 25!

[mstephens]

Just to fill in details...
My Suburban is a 2007 1500 4WD w/5.3L/Auto/4:10 gears. It has 83,000 miles. We use it 75% for towing.

[dkottum]

mstephens, thats a pretty young vehicle in my world. I'm guessing you don't tow an enormous amount of miles per year, like most of us. Hard to justify a trade to only get a few more miles a gallon, and if that margin is supplied by more expensive diesel fuel, even less justification.

doug k

[MrUKToad]

Running one of the smaller TVs around here, I'm always interested in its gas mileage compared to that of its more hefty cousins.

My TV is a 3.5 litre, V6 Toyota Sienna (8 seat) with a six speed auto transmission. Its curb weight is 4735lbs and it develops 266 HP. My trailer is a 2011 28' Serenity, claimed top weight 7300lbs.

I travel on mostly flat terrain and have either two adults plus 70lb dog or three adults, one pre-teen plus the dog when travelling.

Last year over 5966 miles I averaged 12.5mpg (US). My best single trip was 14.8mpg over 156 miles, travelling with four people on a fairly flat Provincial road, sticking mostly to the 50mph limit. There was no wind and the weather was warm. I did the same trip last Friday, two people plus dog, driving into a stiff headwind and sometimes nudging 56mph and I recorded 12.3mpg

My worst trip last year was over 352 miles in reasonably flat terrain, in driving rain and into a head wind with four people on board and doing 62mph as an average, I recorded 10.4mpg.

My figures would suggest that load (people plus stuff) has no marked effect on gas mileage but that keeping the speed down and travelling without a head wind does. I struggle in the same way that everyone else does in the strong winds, despite the TV being fairly aerodynamic.

My real gain, though, is the 28mpg I get (as an average) when not towing.

None of these figures are very scientific but they do highlight speed and aerodynamics rather than weight/load as the key factors for better gas mileage.

[Pillow]

Maybe it could be stated like this. Suppose one were to design a TV based on these goals:
- 25 FC
- Cruise at 60 MPH
- Climb grades at 50 MPH (or "safe speed" let's say)
- Get 15 MPG over all

They did. It is the 96-99 Gm Suburban with the 6.5TD or the Ford Excursion with the 7.3TD.

It kills me that Ford and GM have not added a small diesel to the line up for the 1500/150 series family movers... Or even the Duramax in a 2500 Burb!

My wifes Escalade ESV can't get 15 unloaded much less with anything hitched up. She has pulled a cargo trailer a few times and ends up at about 11 MPG. The LS engine is awesome unloaded, but suffers terribly when towing.

You can engine swap in a Duramax/Allison combo if you want. There are a few places that offer the service.

IMO with 75% towing in mind, it is worth the effort to go diesel.

FWIW at reasonable speeds (don't go over 65) my Burb does 20+ highway. City/mixed 15-16. Towing about 14+ on the highway. But this is with a few modifications, not stock.

Add: My trailer is about 5000 pounds, so not a heavyweight.

[Pillow]

MrToad,

You can't tow with that! LOL I had to do it.

My real gain, though, is the 28mpg I get (as an average) when not towing.

Amazing! Years ago the minivans with V-6 motors didn't fair much better than the SUVs. That MPG is better than most 4 cylinder sedans!

[JamuJoe]

I was unhappy when my mpg dropped to 13.5 in strong headwinds and temps > 100º down south this summer. I normally get 15-17 mpg when towing our FC23FB at 60 mph with our 08 Jeep Grand Cherokee 3.0L Diesel (full time 4WD, 370 ft lbs torque, non-towing avg 23.5 mpg). The best part is, we really like the vehicle whether towing, driving off road or running around town. That's the key - if you like your vehicle, and can live with the mpg, go forth and enjoy your adventures. If it's time for a change, there are good choices out there with increasing fuel efficiencies.

[mstephens]

Originally Posted by MrUKToad

Running one of the smaller TVs around here, I'm always interested in its gas mileage compared to that of its more hefty cousins.

My TV is a 3.5 litre, V6 Toyota Sienna (8 seat) with a six speed auto transmission. Its curb weight is 4735lbs and it develops 266 HP. My trailer is a 2011 28' Serenity, claimed top weight 7300lbs.

I travel on mostly flat terrain and have either two adults plus 70lb dog or three adults, one pre-teen plus the dog when travelling.

Last year over 5966 miles I averaged 12.5mpg (US). My best single trip was 14.8mpg over 156 miles, travelling with four people on a fairly flat Provincial road, sticking mostly to the 50mph limit. There was no wind and the weather was warm. I did the same trip last Friday, two people plus dog, driving into a stiff headwind and sometimes nudging 56mph and I recorded 12.3mpg

My worst trip last year was over 352 miles in reasonably flat terrain, in driving rain and into a head wind with four people on board and doing 62mph as an average, I recorded 10.4mpg.

My figures would suggest that load (people plus stuff) has no marked effect on gas mileage but that keeping the speed down and travelling without a head wind does. I struggle in the same way that everyone else does in the strong winds, despite the TV being fairly aerodynamic.

My real gain, though, is the 28mpg I get (as an average) when not towing.

None of these figures are very scientific but they do highlight speed and aerodynamics rather than weight/load as the key factors for better gas mileage.

28 MPG? Our new 11 Escape V6 only gets 20. 28 solo, 12 towing is interesting compared to my 12/10.6

[barts]

Originally Posted by Denis4x4

When the California Air Resources Board (CARB) was formed in the 1960's to combat smog causing emissions, it led to the inclusion of eco-politics. That has cost the American vehicle buyer tens of thousands of dollars to please a voter block that is selfish and could care less about people outside their elite circle.

So far this year, it has cost me almost $3500 to repair the damage ethanol has caused to my boat and collector cars.

California desperately needed pollution controls on cars; the air in LA was just plain toxic. I remember - I lived there as a kid. You could not see the hill from Whittier... and it's crystal clear there most days now.

The inclusion of ethanol does help reduce emissions (it adds oxygen to the fuel), but the reason we have so much of it in our gas is that it is a subsidy for the corn growers. So it's not eco-politics - it's farm state subsidies for large corporate growers.

- Bart

[JamuJoe]

Originally Posted by Wayward

If gas prices are moving you to a new tow vehicle that gets better mileage, buy it soon! The same thing that has driven up the gas prices (money printing) is going to add $3-5K to a decent sized truck over the few years (inflation due to devalued dollar).

Replacing the crime syndicate running the Treasury and the Fed will do more to return the freedom of the road, than replacing our TVs.

IOW... treat the cause rather than the symptom.

Well, this is off topic, but note that inflation is currently at only 1.4% (lowest yearly avg. since 2002) and fuel prices are lower than when I bought my vehicle in 2008. With the rebuilding of our highways and National Park roads over the last two years, travel is better than it's been for a long time!

[Wabbiteer]

umnn - My newspaper buried the story around page 5 in the business section that producer prices were up 1.4% in August - 22% annualized...

The mileage factor is important for this owner - the cash capital expenditure of outright vehicle purchase was a long term budget goal, however the fuel costs dipping into future limited income is painful. Using my earlier non-airstream travel fuel budget with the trailer towing 9.0 to 12mpg and the current fuel costs all signs point to be able to drive from one interstate rest stop to the next one - once per day.

I hear the whisper here that lower towing speeds are key to better mileage. I'm a great believer in 9pm to 6am distance driving & holding the speed at 53-57mph... Time I have oodles of, cash to cover $100+ fill-ups every 200 miles I don't have. ('99 F-150 4X4 5.4L)

9hr x 50mph = 450mi and 12mpg or 37.5gal or $150 @ $4ga.
9hr x 60mph = 540mi and 9.5mpg or 56.8gal or $252 @ $4ga.

So that is 90 miles make-up driving @ 12mpg = 7.5gal or $30 @ $4ga.

After 540 miles there is a $72 real dividend in my checkbook that will buy 18 gal or 216 miles range by adding less that two hours to the travel time.

Now if I could only count on 15 or 18mpg while dragging, errr.. towing my Airstream

[OilnH2o]

An interesting thread - I tow with my 2001 Sube with the 5.3 and 3.83 rear end (and 4wd). We have gotten as high as 13.5 and as low as 11.6 - so I imagine that's really averaging right at 12 mpg or maybe a little better. (I think it's difficult to know for sure since there's gotta be error in each fill-up and mileage calculation.) That's 65 mph and occasionally 70 on the interstates, but it seems to me that we've noticed lower mpg's when we're on the interstates and higher on two-lane roads. I'm wondering if it's the 4.11 rear end (or 4.10?) that might be making some of that difference?

[Phoenix]

Just personal experience, but in my case, lower interstate mileage was due to higher cruise speeds (and thus, higher wind resistance), and additional fuel wasted speeding up to pass and then slowing down afterwards. With ST tires, I didn't want to cruise at 70-75 mph; so I would speed up briefly to pass, then slow to 65 afterwards. However, the higher cruise speed meant that I was constantly overtaking slower cars, and having to speed up to pass them.

Reducing cruise to 55 mph allowed me to maintain a constant lower speed that reduced wind resistance and eliminated the constant speeding up and slowing down. And, similar fuel economy was achieved on lesser used two-lane highways, because of lighter traffic where 55 mph could be maintained with no passing.

During the Arab oil embargo, the US Government imposed a nationwide speed limit of 55 mph to reduce fuel consumption. That speed is still valid today, if one chooses to use it.

=================

For background info on the Arab oil embargo of 1973, see link below:

1973 oil crisis - Wikipedia, the free encyclopedia

[AtomicNo13]

I think the smart money is on an older TV. I have an 01 v10 Excursion. It returns 15 MPG towing my triple axle. Excellent condition for around $6000. Even at 15 MPG I can afford all the $5 a gallon gas since I'm not in $60k for a new diesel pu. Very pleased with my choice/ decision.

[perryg114]

How much does Ethanol reduce emmissions? Does anyone balance the equation of energy in versus energy out? Also there is the fact the Ethanol seems to reduce gas miliage about 10% which causes you to burn 10% more gas which totally negates the stuff being in there. Yes I know if you look at BTU content the 10% ethanol should not lower gas miliage but it does. It probably has something to do with combustion temperatures. I have had to clean the carbs twice this year in my motorcycle because of ethanol in the gas. It has 4 carbs and they are a pain to remove. Ethanol is corrosive and it makes the gas go stale much quicker.

Perry

Originally Posted by barts

The inclusion of ethanol does help reduce emissions (it adds oxygen to the fuel), but the reason we have so much of it in our gas is that it is a subsidy for the corn growers. So it's not eco-politics - it's farm state subsidies for large corporate growers.

- Bart

[perryg114]

How are you getting 15 MPG towing with a V10 Excursion? Mine won't get 15 MPG empty. It is a good cheap tow vehicle. I love mine even at 9 MPG towing my 31 ft trailer. That is towing 65-70 MPH. Slowing down might get me to 10 MPG. You must have a light foot and the 3.73 rear end.

Perry

Originally Posted by AtomicNo13

I think the smart money is on an older TV. I have an 01 v10 Excursion. It returns 15 MPG towing my triple axle. Excellent condition for around $6000. Even at 15 MPG I can afford all the $5 a gallon gas since I'm not in $60k for a new diesel pu. Very pleased with my choice/ decision.

[ElCamino Man]

^^^ Thats what I was about to say lol. V10s are notoriously gas hogs. Iv honestly never heard of a v10 getting 15 empty...

[mstephens]

Originally Posted by OilnH2o

An interesting thread - I tow with my 2001 Sube with the 5.3 and 3.83 rear end (and 4wd). We have gotten as high as 13.5 and as low as 11.6 - so I imagine that's really averaging right at 12 mpg or maybe a little better. (I think it's difficult to know for sure since there's gotta be error in each fill-up and mileage calculation.) That's 65 mph and occasionally 70 on the interstates, but it seems to me that we've noticed lower mpg's when we're on the interstates and higher on two-lane roads. I'm wondering if it's the 4.11 rear end (or 4.10?) that might be making some of that difference?

I am glad to hear from someone with the same car using a 3:83 gear. I suspect my 4:10 is one of the problems. Something to think about.

[ElCamino Man]

Threadjack!

Im debating swapping my 3.55s for 4.10s though. 4.10s are a "towing" gear, 3.73s are kinda in the middle, and 3.55s are more of a cruising gear. Anything less makes for a DOG when towing but good mpg unloaded. I dont think youll see too much of a gain in mpgs to justify swapping out a $300 set of gears

[Aage]

Originally Posted by mstephens

Just to fill in details...
My Suburban is a 2007 1500 4WD w/5.3L/Auto/4:10 gears. It has 83,000 miles. We use it 75% for towing.

Have you ever considered using your Suburban 100% for trailering, then buying a new "daily driver" like a Prius C for $18,000?

You would have a lot more fun driving, and get an overall 53 mpg. I think that your service costs would drop, too.

[ElCamino Man]

^^^ He's gotta point! Or if moneys tight, you can get a semi-used Jetta TDI @ 45 mpg for under $10,000! Or a used Prius lol.