Why is winter *highway* mpg so low?

[inline_five]

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.

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[MavMeister25]

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’ve noticed the same thing. Although I just got mine and I’ve ONLY driven in the winter on the highways. I’m getting 25-30 mpg on highways. I also wonder why this is the case since technically it shouldn’t be drawing from the hybrid battery which is affected by low temps—and therefore should be getting the estimated 33 mph highway. What gives?

Btw, do you have the AWD? I have the FWD.

 

[Deb from MN]

mine is also down to about 23, wonder if some gas stations have different blends of gas?

 

[MavMeister25]

mine is also down to about 23, wonder if some gas stations have different blends of gas?

What mpg do you get on highways in the summer? And secondly, do you have the hybrid FWD or AWD?

 

[23grayXLT84]

Lots of things can impact highway mpg , speed, wind direction, tire pressure, winter blend gas.....as well as cold air
Cold air is denser which increases your drag.

 

[Deb from MN]

What mpg do you get on highways in the summer? And secondly, do you have the hybrid FWD or AWD?

42-45 summer hybrid fwd

 

[MavMeister25]

42-45 summer hybrid fwd

On the highway??????

 

[Deb from MN]

On the highway??????

I'm not a speed freak when on hwy, and don't drive much anyway (work from home)

 

[Rowerwet]

Cold air is denser, this requires more fuel to be injected to keep the correct 14:1 air/fuel ratio.
Cold air is denser, this means slightly more drag on your brick shaped truck.
You're running the cabin heater and the only heat source is the engine, so you'll have the engine running just to produce heat even when it would be off in moderate temperatures. The majority of heat from combustion in an ICE engine goes out the tailpipe, so most of this extra gasoline burned for heat is wasted, with possibly 20% going into the engine coolant and then into the greater core and then the cabin air.
You're running seat/steering wheel/windshield wiper heaters (if equipped), and those all require the engine to run more to recharge the batteries that power them.
You're probably driving in the dark more and that requires more lights to be on, which also use more battery energy.
Your tires are stiffer from cold, and the pressure might drop a couple pounds overnight, this robbs energy from the engine requiring more engine power to go the same speed.
The winter time gasoline mix usually has the highest percentage of ethanol in it, and ethanol has less energy per gallon than gasoline. This means that possibly 10% of what you pump into your tank has less energy in it, and this of course requires more fuel to be burned.

 

[Scupking]

Simple. Winter blend gas and cold weather.

 

[nospam56]

How cold was it. ICE engines are always worse in the winter and the colder it is, the bigger the difference.

 

[Jeff D.]

I don't know what weight fluid Ford uses in their transmissions and differentials, but I know in other/heavier vehicles, the grease in those can take a long time to warm up enough to thin out. That adds addtional friction until it does. Even wheelbearing grease takes some amount of time of spinning before it'll allow the wheel end to spin freely.

Just another small factor to add in to the others mentioned.

 

[inline_five]

What mpg do you get on highways in the summer? And secondly, do you have the hybrid FWD or AWD?

Not who you quoted but I get around 35 mpg highway in the warmer months going 75, 36-37 mpg going 70. It's the same highway route of which 98% is highway speed at 70 or 75 depending on my time pressure for 180 miles.

My tire pressure is always at or above 40 psi. Today I actually filled it to 43 psi before leaving.

I'm wondering if the hybrid is just that sensitive to anything that gives it a mpg hit and cumulatively the sub-freezing temps all add up to major losses. But we're talking 30% loss here. Crazy.

 

[AF Blue]

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.

EPA estimate: 33 highway
EPA Highway Test Speed: not >65mph AFAIK .. but not gonna even search (60mph is a guess)

Winter blend gas ... tends to drop MPGs
Hybrid Battery use in extreme temps usually pushes ICE into use more.


AKA ...i'm not an engineer, but when i read your post i see "normal operation" for Hybrid Mav.
You are not far off from EPA

 

[MavMeister25]

But we're talking 30% loss here. Crazy.

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?

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