How to improve Highway MPG?

[HowardN]

We have a several week old 2010 Hybrid and have taken it on 2 trips that were nearly all highway driving. On the most recent trip (NY Thruway - 380 miles), we only achieved 25.5 MPG - driving at 72 MPH without AC and with windows closed. The mileage is correct as we filled the gas tank before the trip and had to refill it after. I had not expected the mileage to be this poor - it is actually no better than my 2005 V6 Dodge Caravan. While a slower drive might give better mileage, this is not a feasible option on that road.

 

Any and all ideas appreciated.

[NewNole2001]

We have a several week old 2010 Hybrid and have taken it on 2 trips that were nearly all highway driving. On the most recent trip (NY Thruway - 380 miles), we only achieved 25.5 MPG - driving at 72 MPH without AC and with windows closed. The mileage is correct as we filled the gas tank before the trip and had to refill it after. I had not expected the mileage to be this poor - it is actually no better than my 2005 V6 Dodge Caravan. While a slower drive might give better mileage, this is not a feasible option on that road.

 

Any and all ideas appreciated.

Something must be wrong. I generally get at least 33 mpg doing 80, and 36-40 doing 65-70.

[lolder]

Are you sure the transmission was in "D" and not "L"? It's easy to select the wrong position. 36-40 is normal. What did the trip summary screen say at the end of each run?

[HowardN]

Are you sure the transmission was in "D" and not "L"? It's easy to select the wrong position. 36-40 is normal. What did the trip summary screen say at the end of each run?

 

When We started outbound, I noticed the shift was in Low, and changed it. For the return trip, I made sure it was in Drive - but we used up a full tank of gas with each leg - 15.5 gallons to refill for a 380 mile trip - so I'm sure of the MPG (actually, I didn't look at the summary screen, but since we usually take 2 bathroom breaks, the summary would have only been for partial legs). I'll check it at the next trip.

 

To have the car in LOW would make sense, but it shouldn't have been. Should I have the gear position checked?

[VonoreTn]

might give better mileage, this is not a feasible option on that road.

 

Any and all ideas appreciated.

 

Something is definitely wrong. Change your leaf screen to a bar graph, so you can start getting real feedback on your driving techniques. I have 23 thousand miles on my 2010 FFH and I keep full records based on every fill up. I can send you the Excel sheet with all that info. I never got under 35 and I am averaging 39 for the entire year. I usually get over 40 on trips.

[HowardN]

Something must be wrong. I generally get at least 33 mpg doing 80, and 36-40 doing 65-70.

 

I expected the same. I'll check to see what RPMs I'm getting on the highway next time (it's not on my current display, but I can bring it up). Something seems wrong.

[HowardN]

Something is definitely wrong. Change your leaf screen to a bar graph, so you can start getting real feedback on your driving techniques. I have 23 thousand miles on my 2010 FFH and I keep full records based on every fill up. I can send you the Excel sheet with all that info. I never got under 35 and I am averaging 39 for the entire year. I usually get over 40 on trips.

 

 

As a newbie to the thousands of settings available for the dashboard, how do I do what you suggest? (Or should I just browse through the settings?)

[JimFFH]

Check your tire pressure, you might be running PSI in the 20s or something. Tire PSI seems to make a big difference. Going down those big hills in NY, are you seeing lots of 60+ readings? If you don't get out of the gas or use a light foot on a downgrade, then the gas engine won't shut down and kill your mileage.

 

How is it behaving besides these 2 trips?

 

I'd take it in to the dealer if it continues to be that low.

[HowardN]

Check your tire pressure, you might be running PSI in the 20s or something. Tire PSI seems to make a big difference. Going down those big hills in NY, are you seeing lots of 60+ readings? If you don't get out of the gas or use a light foot on a downgrade, then the gas engine won't shut down and kill your mileage.

 

How is it behaving besides these 2 trips?

 

I'd take it in to the dealer if it continues to be that low.

 

I've been getting around 40 MPG on short city trips. Every time I would go down a hill, the readings do go right up to 60+ - my wife would joke that I was trying to boost the readings when that would happen (little did she know they were boosting from 25!). I used cruise control on my highway trips - I would have thought that would have helped with MPGs - is that ncorrect?

[JimFFH]

I don't know about cruise control and how the car acts, I haven't used it yet. Others with more experience may be able to offer up some more help. Did you have a carload full of people? and trunk full of luggage? Roof rack?

 

Good to know at least your shorter trips are reasonable.

 

I have a 2005 Town and Country, and I hate the way cruise control acts with hills. It'll nearly drop 5mph, then downshift and roar like crazy to get back up to speed and then some. Maybe the Fusion cruise control is affecting your highway miles when dealing with these hills, where as in Florida cruise control wouldn't have that issue. Definitely check/properly inflate your tires first. I personally run mine at 40PSI.

[lolder]

As a newbie to the thousands of settings available for the dashboard, how do I do what you suggest? (Or should I just browse through the settings?)

There are really only four main dash displays. 'Enlighten" is the only one that shows RPM. You should probably read the Owners Guide thoroughly and spend about a 1/2 hour getting familiar with the displays. All show the shift position. If you are in "L", there is a lot of engine braking and higher rpms.

[lolder]

Remember, there are 6 different fuel economy measurements available:

1) Instantaneous MPG gauge

2) Average MPG display resettable from an information screen

3) Long Term Fuel Economy displayed at bottom of trip summary resettable in menu

4) Bar graph time intervals, if displayed (or leaves)

5) Trip summary MPG at end of each vehicle operation.

6) Distance to empty display which uses a running average of the last 500 miles to compute range to 1 gal remaining.

There should never be any surprises with all this info available. You can see head and tail winds, wet roads, drafting in traffic effects on the instantaneous MPG display. The bar graphs show you the effect of long hills, speed changes, temperature changes.

Be sure to look out the windshield.

[savngas]

Driving in the hills of West Virginia and especially on Interstate 77 between Beckley and Charleston I use cruise control all of the time.

Cruise on uphill runs is smooth and steady, no lag. Cruise on downgrades creeps up pretty fast but if you pull to "low" it will hold set speed downhill also. Easy to forget you are in low so you have to keep that in mind. My highway mileage with cruise, AC is averaging 36-37 mpg.

[HowardN]

Remember, there are 6 different fuel economy measurements available:

1) Instantaneous MPG gauge

2) Average MPG display resettable from an information screen

3) Long Term Fuel Economy displayed at bottom of trip summary resettable in menu

4) Bar graph time intervals, if displayed (or leaves)

5) Trip summary MPG at end of each vehicle operation.

6) Distance to empty display which uses a running average of the last 500 miles to compute range to 1 gal remaining.

There should never be any surprises with all this info available. You can see head and tail winds, wet roads, drafting in traffic effects on the instantaneous MPG display. The bar graphs show you the effect of long hills, speed changes, temperature changes.

Be sure to look out the windshield.

 

Because we had to refill the tank on the trip out - which I didn't expect, having driven this route many dozens of times before - I watched the readings on the way back (other than the leaves, which told me nothing - and I've replaced them with the bars). I was struck by the lack of "instant MPG" fluctuations - mostly between 20 and 30, rarely up toward 60. And the ultimate proof of MPG was the empty gas tank before we reached home. On reflection, the car "acted" like it was in low, but I know that it was displaying "D". I need to take another interstate drive and see what happens. By the way, the dealer said "it's normal for the break-in period - up to 10,000 miles - to get that mileage".

[HowardN]

Driving in the hills of West Virginia and especially on Interstate 77 between Beckley and Charleston I use cruise control all of the time.

Cruise on uphill runs is smooth and steady, no lag. Cruise on downgrades creeps up pretty fast but if you pull to "low" it will hold set speed downhill also. Easy to forget you are in low so you have to keep that in mind. My highway mileage with cruise, AC is averaging 36-37 mpg.

 

I was certain the car wasn't in low gear, but the MPG behavior makes me wonder. This trip on I-90 from Erie to Saratoga should have been flatter than your I-77 experience (I've been through there - the hills and curves at night are impressive) - I'll need to do some more testing on the highway.

[Buster1]

A couple things. Our FFH took a good 2-3 thousand miles before the MPG really got good and solid. My first few tanks were in the 25-30 MPG range generally.

 

Secondly, the manual recommends against going one speed constantly during engine break in (for the forst 500 miles or so). I would not use cruise control during this period.

 

Lastly, what's your driving style? Do you "punch it off the line" like lots of people? That will hurt the mileage significantly. I also noticed huge differences in mpg on the hwy (I do mostly hwy driving) between 50-60mph and 60-70mph. The few times I went 75+mph for an extended time the car's mpg was closer to my old car...27-31mpg.

[lolder]

Because we had to refill the tank on the trip out - which I didn't expect, having driven this route many dozens of times before - I watched the readings on the way back (other than the leaves, which told me nothing - and I've replaced them with the bars). I was struck by the lack of "instant MPG" fluctuations - mostly between 20 and 30, rarely up toward 60. And the ultimate proof of MPG was the empty gas tank before we reached home. On reflection, the car "acted" like it was in low, but I know that it was displaying "D". I need to take another interstate drive and see what happens. By the way, the dealer said "it's normal for the break-in period - up to 10,000 miles - to get that mileage".

The dealer is wrong, it's not normal to get significantly lower mileage when new. Some have reported it but I observed no differences with mine except the learned improvement in driving habits. The instant gauge fluctuates all the time even on flat roads and steady speeds. The cruise control will vary the throttle MORE than your foot. Driving in hilly country without it will improve mileage only if you let the speed deteriorate a lot going up hills with the constant pedal pressure technique. Driving without cruise on is usually more trouble than it's worth. There's a big difference between "D" and "L" observable during any operation except heavy acceleration. Switch back and forth to test it. There are economy losses with high speeds, headwinds, wet roads COLD temperatures, heavy AC use. At the worst you should see mid to low 30's mpgs. Cruising at 70 mph in summer weather should yield close to 40 mpg, sometimes more in traffic. Traffic creates a tailwind-like air flow. You may get better mileage drafting an SUV at a safe distance at 75 mph than cruising by yourself at 70 in the right lane.

[HowardN]

A couple things. Our FFH took a good 2-3 thousand miles before the MPG really got good and solid. My first few tanks were in the 25-30 MPG range generally.

 

Secondly, the manual recommends against going one speed constantly during engine break in (for the forst 500 miles or so). I would not use cruise control during this period.

 

Lastly, what's your driving style? Do you "punch it off the line" like lots of people? That will hurt the mileage significantly. I also noticed huge differences in mpg on the hwy (I do mostly hwy driving) between 50-60mph and 60-70mph. The few times I went 75+mph for an extended time the car's mpg was closer to my old car...27-31mpg.

 

We had driven the car about 1000 miles before this trip - mostly local driving. I tend to not accelerate rapidly (the old "fuel-efficient" way) and I use cruise control on the interstate, although I am frequently switching out of it because traffic around Buffalo, Rochester and Syracuse doesn't allow anyone to keep the same speed for a long time. I usually go around 72 MPH on the highway - it's less visible to the state police!

 

It may take some time and observation to figure this out. I'll see what the next few weeks brings and ask again if it's not beeter.

[HowardN]

The dealer is wrong, it's not normal to get significantly lower mileage when new. Some have reported it but I observed no differences with mine except the learned improvement in driving habits. The instant gauge fluctuates all the time even on flat roads and steady speeds. The cruise control will vary the throttle MORE than your foot. Driving in hilly country without it will improve mileage only if you let the speed deteriorate a lot going up hills with the constant pedal pressure technique. Driving without cruise on is usually more trouble than it's worth. There's a big difference between "D" and "L" observable during any operation except heavy acceleration. Switch back and forth to test it. There are economy losses with high speeds, headwinds, wet roads COLD temperatures, heavy AC use. At the worst you should see mid to low 30's mpgs. Cruising at 70 mph in summer weather should yield close to 40 mpg, sometimes more in traffic. Traffic creates a tailwind-like air flow. You may get better mileage drafting an SUV at a safe distance at 75 mph than cruising by yourself at 70 in the right lane.

 

I agree with you. But I don't remember a lot of instant gauge fluctuation on this trip (though I wasn't watching it too closely). I'll do some self-testing in the next few weeks. Though your suggestion for drafting is tempting, with my luck, the New York State Police will pull BOTH of us over!

[engratsea]

I have found a large drop after around 65 MPH on the highway. Around 60 MPH I average around 46, around 65 MPH I average around 40, around 70 MPH I am in the mid 30s.

 

However, I have also found that on similar trips the hwy MPG is significantly different; like the car has found a grove and other times it seems to run harder. Anyone seen these differences?

 

The bottom line is if you really want better MPG on the hwy you need to slow down.

[VonoreTn]

.............. I was struck by the lack of "instant MPG" fluctuations - mostly between 20 and 30, rarely up toward 60....................

 

That right there is very suspicious behavior, mine will shoot up to 60( 60+ on the "i" (information tab HEV)) if I let off the gas under any condition, even going up a hill.

 

Practice this first in your garage: move the gear lever from drive to neutral (take care not to hit reverse, without looking, practice). Hitting reverse accidentally will not destroy the transmission in a FFH, but it is solidly not recommended to hit reverse while driving forward. Hitting reverse in a more conventional car while going forward could destroy the transmission, so be very careful with the concept. OK, now that you have this down, try it on a slight downgrade at any speed on the highway. the instantaneous mpg will definitely go to 60 in neutral. If you see a huge difference, like suddenly going from 30 mpg to 60 when you go to neutral, you may have some kind of driveline drag, similar to being in low gear. Don't tell the dealer I suggested any of this ;-) You are on your own. And it is only a test, not a driving strategy, since if your FFH is working right, it almost does the same thing automatically when you take your foot off the gas. Being able to put your car in neutral is a safety maneuver, since it is the recommended procedure should a generic car ever have a full throttle failure event while driving. So it is not heresy to recommend that drivers be familiar with the concept and procedure.

 

If your FFH still doesn't hit 60 mpg in neutral going down a hill, you may have dragging brakes, or a very bad toe-in or toe-out wheel alignment condition.

[HowardN]

The dealer is wrong, it's not normal to get significantly lower mileage when new. Some have reported it but I observed no differences with mine except the learned improvement in driving habits. The instant gauge fluctuates all the time even on flat roads and steady speeds. The cruise control will vary the throttle MORE than your foot. Driving in hilly country without it will improve mileage only if you let the speed deteriorate a lot going up hills with the constant pedal pressure technique. Driving without cruise on is usually more trouble than it's worth. There's a big difference between "D" and "L" observable during any operation except heavy acceleration. Switch back and forth to test it. There are economy losses with high speeds, headwinds, wet roads COLD temperatures, heavy AC use. At the worst you should see mid to low 30's mpgs. Cruising at 70 mph in summer weather should yield close to 40 mpg, sometimes more in traffic. Traffic creates a tailwind-like air flow. You may get better mileage drafting an SUV at a safe distance at 75 mph than cruising by yourself at 70 in the right lane.

 

I haven't had a chance to take another highway drive yet, but as I've been watching the MPGs during city driving I've noticed that my assumption about the role of the electric engine may be wrong. I assumed that the electric engine was a "co-contributor" to speed and acceleration, but it appears to only help maintain speed when "coasting" or having an even speed. My drive from work to home is level to somehat uphill and I cannot achieve more than 16-20 MPG ever on that route. I can get 37-40 MPG to work (because it's mostly downhill). I think my expectation was based on what the electric car motors do (as in "Who Killed the Electric Car")- but I'm surprised that my Fusion Hybrid electric motor does not accelerate the car from a stop nor seem to help the gas engine when going up hills. I thought it would have been more "synergistic".

[akirby]

I haven't had a chance to take another highway drive yet, but as I've been watching the MPGs during city driving I've noticed that my assumption about the role of the electric engine may be wrong. I assumed that the electric engine was a "co-contributor" to speed and acceleration, but it appears to only help maintain speed when "coasting" or having an even speed. My drive from work to home is level to somehat uphill and I cannot achieve more than 16-20 MPG ever on that route. I can get 37-40 MPG to work (because it's mostly downhill). I think my expectation was based on what the electric car motors do (as in "Who Killed the Electric Car")- but I'm surprised that my Fusion Hybrid electric motor does not accelerate the car from a stop nor seem to help the gas engine when going up hills. I thought it would have been more "synergistic".

 

It will power the car all by itself but only under very light acceleration. I suspect it's not the car but you're driving style.

[lolder]

I haven't had a chance to take another highway drive yet, but as I've been watching the MPGs during city driving I've noticed that my assumption about the role of the electric engine may be wrong. I assumed that the electric engine was a "co-contributor" to speed and acceleration, but it appears to only help maintain speed when "coasting" or having an even speed. My drive from work to home is level to somehat uphill and I cannot achieve more than 16-20 MPG ever on that route. I can get 37-40 MPG to work (because it's mostly downhill). I think my expectation was based on what the electric car motors do (as in "Who Killed the Electric Car")- but I'm surprised that my Fusion Hybrid electric motor does not accelerate the car from a stop nor seem to help the gas engine when going up hills. I thought it would have been more "synergistic".

I mentioned before "drafting at a safe distance" only.

Whenever there is ample power demand, Ford wants the ICE to run, not the electric motor (they are called "motors", not "engines"). The EV is used for transient acceleration pulses until the computer can increase the ICE rpm for more power.

It is also used for regenerative braking, and duty-cycling the ICE on and off at lower speeds for better efficiency. You can only see the power of the traction motor in reverse. Go to a big open area and carefully, briefly floor it in reverse. The ICE will probably start but it cannot provide power to the wheels in reverse. It can generate electricity which together with the HVB will power the traction motor in reverse. The power is substantial. You can't do this in "D" because the software won't permit it. EV mode is LESS efficient when higher power is required. This is a gas powered vehicle, not electric. The EV components only assist the ICE in efficiency. Plug-in-hybrids are completely different in requirements than the FFH and Prius.

Edited October 22, 2010 by lolder

[VonoreTn]

I mentioned before "drafting at a safe distance" only.

 

 

You mention drafting, let me tell you my experience. I think that there is no doubt that drafting improves mileage. And the closer to the truck you get, the better it works. 70 feet is better than 100 feet. I'm talking maybe 2-4 mpg better. But I learned my lesson in Missouri, where a truck for an instant went onto the shoulder, threw up some gravel, and cracked my windshield. So I recommend don't draft.

 

Factor in the the cost of a new windshield when you do you your calculation for how much you will save in gas expense. Plus it requires too much focus as you can't take your eye off that truck for an instant. At 70 mph you are one second behind a truck at 103 feet. Not enough reaction time should something go wrong. Nor can you see the truck pass over a big chunk of truck retread on the road, which also can, in an instant, do hundreds of dollars of damage to your vehicle.

 

I am still getting over 40 mpg on trips not drafting, going 70, with speed control and the AC on, which is plenty good enough for me. Last winter my mpg went significantly below 40 for a winter trip to Colorado. Then it improved after the dealer made the "brake sensitivity" free dealer campaign adjustment. But another variable was that it was the only really cold weather trip that we have made. Maybe it was the cold weather, I'll be watching it closely this winter.