Why is winter *highway* mpg so low?

[inline_five]

Right!? That’s a huge drop in mpg. I’m glad I live in the South where it rarely goes below freezing even in winter.

Is this your first winter owning the Mav?

I live in central NC, we've had a month+ of well below average temps. I've owned it two winters now, bought in Sept '23 however didn't drive it much that winter.

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[The Real Maverick]

I have a '23 hybrid, and drive a normal highway route of 180 miles @ 70-75 mpg. My average speed is around 74.

Did it today, first time in cold temps (28°F weather) and got 27 mpg. Normal is 35-36 over the summer months. Keep in mind tire pressure was ~40 on all four (just filled them prior to trip).

Curious why low temps effect the hybrid mpg so much? Heat being on shouldn't bring it down from where it is in the summer, as the engine is running 100% of the time at ~75 mph.

A lot of good answers here.

Here's one more:

ALL CARS AND TRUCKS GET LOWER MPG IN WINTER but hybrid cars and hybrid drivers pay attention to this much more precisely.

Also consider: a "gasser" F-250 may drop from 15 MPG summer to 12 MPG winter, and most owners will not notice or complain about a 3 mpg drop.

The Hybrid Mav may get 42 MPG summer and 33 MPG winter. Wow you say! Most owners WILL notice and complain about a 9 mpg drop.

But it is 20% drop FOR BOTH VEHICLES.

Also consider your hybrid is STILL saving gas in winter compared to your "old" gas only vehicle.

 

[Toddman45]

As op said, it's the Winter Blend Gas.

 

[TheQuixotic1]

I have a '23 hybrid, and drive a normal highway route of 180 miles @ 70-75 mpg. My average speed is around 74.

Did it today, first time in cold temps (28°F weather) and got 27 mpg. Normal is 35-36 over the summer months. Keep in mind tire pressure was ~40 on all four (just filled them prior to trip).

Curious why low temps effect the hybrid mpg so much? Heat being on shouldn't bring it down from where it is in the summer, as the engine is running 100% of the time at ~75 mph.

Lower temps drastically effect all vehicles, it just becomes more obvious the more efficient a vehicle is. It also becomes more noticeable and irritating because you bought the vehicle, in part, because of its efficiency.

If you tracked the efficiency of all your vehicles over time you'd see a 20-30% drop in efficiency in peak winter weather across the board.

 

[TonyS]

Lots of people have mentioned the reasons - winter gas, denser air. ICE engine running more to provide heat and hybrid owners really sensitive to gas mileage. I will add one thing:

Do you have the AC on? I'm not sure what it depends on, but if the AC is on to help defog the windshield gas mileage is substantially less. So I make a point of not using the AC in the winter if I'm not having a problem with the windows fogging up. Heat is on as needed. . I'm not freezing or sweating to get a few more MGP. But if the windows are not fogging up it's heat only.

 

[Cherokee]

Prolly the biggest reason/factor my 24’ Eco AWD drops a couple of mpg’s in the winter is my long
fifteen minute warm up’s.
Getting in my Lariat on these super cold single digit mornings at sun rise is so nice.
Cabs all toasty warm as is my seat and steering wheel.
Mirrors all defrosted. Awww it’s a bitchin ride in my book.

 

[bartflossom]

I drive the wife from Dallas to Lafayette, 400 miles, a few times a year and last August with A/C on I got 37 going down and 33.5 coming back. Typical speed 77. Difference due to wind.

Just did the drive mid January and got 32-33.

Next time I drive it I'm going to try and get some ethanol free gas. I know I won't save enough in mileage to make it worthwhile dollar wise, but I'm just curious how big a difference it will make.

 

[Jonny44]

The high-voltage battery also discharges faster and takes longer to charge in colder temps. My old Polestar would show a full-charge range at around 300 miles at temps near freezing and would drop to 150 after a 50 mile drive, without using the hvac system. In warmer temps it would drain more evenly. The hybrid battery is used less, resulting in even lower mpg. I did notice that my Maverick would not go into full electric drive at temps under -15f, no matter which drive mode was being used at any speed.

 

[Caravan to Maverick]

I have a '23 hybrid, and drive a normal highway route of 180 miles @ 70-75 mpg. My average speed is around 74.

Did it today, first time in cold temps (28°F weather) and got 27 mpg. Normal is 35-36 over the summer months. Keep in mind tire pressure was ~40 on all four (just filled them prior to trip).

Curious why low temps effect the hybrid mpg so much? Heat being on shouldn't bring it down from where it is in the summer, as the engine is running 100% of the time at ~75 mph.

Engine has to run more, as you need heat to stay warm. I also own a 23 Ford Maverick. getting 33MPG in the city with very cold temps. Summertime I get 43 to 45 MPG

 

[brokenaxle]

Something else to consider , the fuel will run richer to get the catalytic converter up to temp in colder weather.

 

[inline_five]

Engine has to run more, as you need heat to stay warm. I also own a 23 Ford Maverick. getting 33MPG in the city with very cold temps. Summertime I get 43 to 45 MPG

On highway the engine runs 100% of the time, which is why I wrote *highway* in my title. Should be zero factor.

The high-voltage battery also discharges faster and takes longer to charge in colder temps. My old Polestar would show a full-charge range at around 300 miles at temps near freezing and would drop to 150 after a 50 mile drive, without using the hvac system. In warmer temps it would drain more evenly. The hybrid battery is used less, resulting in even lower mpg. I did notice that my Maverick would not go into full electric drive at temps under -15f, no matter which drive mode was being used at any speed.

Zero factor on highway going 70-75 on flat terrain, you don't use the battery, you use the ICE for sustained highway driving.

Something else to consider , the fuel will run richer to get the catalytic converter up to temp in colder weather.

Only initially on startup not hours into the trip, I drove 2:40. Should only have been a factor in the first 5-10 minutes.

Lots of people have mentioned the reasons - winter gas, denser air. ICE engine running more to provide heat and hybrid owners really sensitive to gas mileage. I will add one thing:

Do you have the AC on? I'm not sure what it depends on, but if the AC is on to help defog the windshield gas mileage is substantially less. So I make a point of not using the AC in the winter if I'm not having a problem with the windows fogging up. Heat is on as needed. . I'm not freezing or sweating to get a few more MGP. But if the windows are not fogging up it's heat only.

No, A/C is off and humidity is very low right now, so should not be running much. I use Auto on low fan setting set to 72°. I did try turning heat off but that did not appreciably change the mpg.

 

[sapperforward]

I have a '23 hybrid, and drive a normal highway route of 180 miles @ 70-75 mpg. My average speed is around 74.

Did it today, first time in cold temps (28°F weather) and got 27 mpg. Normal is 35-36 over the summer months. Keep in mind tire pressure was ~40 on all four (just filled them prior to trip).

Curious why low temps effect the hybrid mpg so much? Heat being on shouldn't bring it down from where it is in the summer, as the engine is running 100% of the time at ~75 mph.

I don't think this is only a hybrid issue I'm in my 24 EB FX4 ( obviously 1st full winter)and I have noticed a 4-7 mpg drop . I did swap out to steelies and winter tires so I don't know how much that's affecting it but my normal mpg is 26~30ish and I'm currently getting 20~24 ish so

 

[inline_five]

I don't think this is only a hybrid issue I'm in my 24 EB FX4 ( obviously 1st full winter)and I have noticed a 4-7 mpg drop . I did swap out to steelies and winter tires so I don't know how much that's affecting it but my normal mpg is 26~30ish and I'm currently getting 20~24 ish so

Are you doing a lot of idling or warming up before driving? I didn't, I opened my garage and started driving. Even so, that shouldn't impact a 180 mile drive appreciably.

 

[MikeS1942]

Just look at your information on your dashboard after a winter drive compared to a summer drive. My hybrid during the summer would run on electric for about a third of the miles. During this winter of very cold weather, I've dropped from 33% electric to about 10% electric. Driving at 75 mph also uses more fuel than driving at 50 mph. Most of this is caused by the heating of the cab, and all the extra heating that is draining the battery. The colder air moving through the radiator causes your engine to have to run more to keep the water warm enough to keep you comfy in your cab. It will get much better in the warmer weather, just like it does for all internal combustion vehicles.

 

[inline_five]

Just look at your information on your dashboard after a winter drive compared to a summer drive. My hybrid during the summer would run on electric for about a third of the miles. During this winter of very cold weather, I've dropped from 33% electric to about 10% electric. Driving at 75 mph also uses more fuel than driving at 50 mph. Most of this is caused by the heating of the cab, and all the extra heating that is draining the battery. The colder air moving through the radiator causes your engine to have to run more to keep the water warm enough to keep you comfy in your cab. It will get much better in the warmer weather, just like it does for all internal combustion vehicles.

Isn't the engine running 100% of the time at 75 mph? I use almost zero electric miles on my 75 mph 180 mile highway drives. I set cruise control to 75 and it just cruises.

I'm comparing summer 75 mph, 180 miles to winter 75 mph, 180 mile drive here. Summer is 35-36 and winter is 26-27.

Just crazy it impacts it that much. That's a 25%-30% drop in fuel efficiency for the same route, same speed, just different temperature. I've not seen that in our Prius.

Found this chart on a Canadian government website, most vehicles show a 7%-12% decline in efficiency:

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