MPG city vs freeway

Discussion in 'Gen 4 Prius Main Forum' started by Buggs1a, Jun 3, 2025 at 2:31 AM.

  1. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    So I have the 2020 Prius L Eco. I read articles and watch vids. Manufactures always rate city mpg higher than freeway. Why? It’s not right. No way ever is city higher mpg then freeway. They have it backwards. I have always gotten WAY more mpg on the freeway than city.

    City has stop and go. You use the accelerator all the time. Slow down. Speed up. Not so on the freeway. You do a consistent speed.

    Freeway gives me over 60 mpg so far. City less then 40.
     
  2. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    8,080
    6,882
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Easy.
    Math and physics.

    In order to answer this question more effectively, let's look at one of the most efficient vehicles ever produced:
    The Dodge Hellcat.

    At idle, it can deliver something like 18? 20? hours of run time.
    However (comma!!!)
    If you mash the 'fun switch' to the floor while the car in in drive?
    This same car will empty over one and a half full Prius fuel tanks in 11-13 minutes....

    @ 203MPH....
     
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    the epa uses a specific testing proceedure, which may or may not come close to real world individual results.
    i can do pretty well in local driving using pulse and glide techniques, coasting to lights and etc.
    it can be exhausting though, and frustrating if there is traffic behind you.
    highway is set it and forget it, but it is mostly engine with a little battery
     
  4. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    To me I find epa if that’s who does these things, wrong and not real world. They drive not like we do. They use slow speeds and flat roads no traffic for testing. Nothing about them is real world. I don’t think.

    I always get way better mpg on the freeway because it’s not stop and go. CC works good. I find city more engine because of stop and go and accelerate more often then using CC on the freeway.

    All I know is my freeway driving gives more mpg then city. I find this backwards to official ratings that never match my driving.

    Be so cool if the car separated city and freeway and gave you mpg for each. Knowing based on gps which is city and which is freeway. This be cool if it could do that.
     
  5. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    8,080
    6,882
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    You need to forget about what other people are saying about YOUR car, including your car's MPG video game
    If fuel efficiency is your goal then run two or three tanks of gas through YOUR car and use a pencil and a hunk of paper to determine YOUR real-world tank average.
    Or?
    You could just relax and enjoy the fact that the G4 is a VERY fuel efficient car.
    Somebody a LOT smarter than I am once said that you can drive a Prius like "an ordinary car" and it will deliver extraordinary mileage.

    My advice?
    (street value: < 0.02 $USD)
    Just drive the car.

    Circle back on this topic in 6 months or so......

    OH....and GET a spare tire!

    YMMV
     
  6. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Unfortunately, it would be impossible for the epa to emulate all the different driving styles and circumstances into one test.
    Being a moderate type of driver most of my life (obeying the rules of the road and accelerating modestly) I have always been close to epa results or better.
    The test is supposed to help with comparing different cars, not predicting what an individual will get
     
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    It’s like buying an appliance, and the sticker tells you about how much it costs to on average.
    But they don’t know how much you’re going to use it, or what your fuel costs are
     
  8. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Yes. Just drive. I do. But I get nervous going slow accel. I want to barely push the pedal off the line. But it’s difficult. Don’t wanna tick off others behind me but want best mpg. I will be gentle but not way too slow. Just drive.

    It just bothers me seeing ratings opposite of real world. They’ve got it backwards. And that upsets me.
     
  9. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

    Joined:
    Oct 28, 2010
    8,080
    6,882
    0
    Location:
    Redneck Riviera (Gulf South)
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    You're just now figuring out that you shouldn't believe everything you read? ;)
     
  10. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I’ve known that for years. I have always been upset about the mpg ratings of cars. They lie. They are not real world like we drivers do.
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    58,683
    40,403
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    There’s reasons why the city mpg rating is better:

    1. Electric-only propulsion can only happen below a certain speed.

    2. Air drag is less.

    3. Lower speeds keep the engine in more efficient range.
     
  12. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Ok then why am I getting way more in freeway?
    Ev only goes 19 mph only. Even though I see article or videos that say up to 31. Bull. I’m talking using the ev button. It’s useless. And there’s stop and go. Acceleration uses the engine. Cc makes all the difference and yiu can barely do that in the city. Then there’s stop and go again. It just do t work like ratings say.
     
  13. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    it has been agreed here that the ev button is almost useless since it first came out
     
  14. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    everything on the net shows hybrids get better city than highway, so i'm at a loss to explain your experience
     
  15. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    26,160
    17,118
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Often someone will come to PriusChat under a misconception that driving EV will be more efficient than when the engine runs.

    If you have a Prime that can be true, because some of your electric power can have come from somewhere else besides the engine.

    In an ordinary Prius, any time you're using electrical power, you're using gas engine power that was inefficiently put into the battery earlier and being taken inefficiently back out now.

    So it turns out that trying to maximize your engine-off driving isn't really a route to good efficiency. The battery serves best as a buffer between momentary surpluses and momentary deficits of gas engine power; you don't beat the efficiency of when the engine is producing just the amount of power needed.
     
  16. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    It’s very simple. What people say means nothing. What is real does. In city it’s as I said. Stop and go. Accelerate all the time. On freeway speed is consistent. With cc that is. So no more stop and go and no accelerate like in city. Your speed is more consistent. I have always had way more mpg on the freeway because of this. But this is just me.

    Right now I’m getting 67.5 mpg on the freeway. City is less than 40 mpg. If my speed is consistent no matter where I am then mpg is higher. There’s no stop and go and less acceleration. Just more consistent. Just me though.

    And I don’t mean to argue. Sorry. Just find official ratings backwards to me.
     
  17. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    26,160
    17,118
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    I made a road trip last summer that passed through Montana and Wyoming, where some posted freeway limits were 80 or 85 MPH.

    That gave me the opportunity to vary my MPG by a factor of roughly two just by choosing what consistent freeway speed to drive.
     
  18. kevinwhite

    kevinwhite Active Member

    Joined:
    Jun 10, 2006
    333
    200
    0
    Location:
    Los Gatos Ca
    Vehicle:
    2017 Prius
    Model:
    Four
    What speed are you going on the freeway? 67mpg sounds much higher than expected.

    For my 2017 gen 4 Prius I would get 52 mag on the freeway doing 65-70mph. For commuting with a mixture of stop and go and expressway running I would get 65-68mpg. For the same commute my 2012 Mazda 3 I would get about 30 mpg or 40mpg on freeway. These measurements are by measuring fuel consumed - not from the dashboard display which is usually a couple of miles per gallon optimistic.

    Although the stop and go traffic makes the efficiency much worse with a conventional vehicle the battery buffers the inefficiency of the Prius engine so that the much lower air resistance results in a higher fuel efficiency (at least for most people and the EPA test).

    The Prius attempts to always use the engine at its optimum power point or not run the engine at all when appropriate. Forcing use of EV mode will usually result in worse efficiency

    kw
     
    bisco likes this.
  19. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,956
    50,946
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    not arguing. you are stating your reality. i understand and can't refute it.
    most everyone else, it's the opposite. i don't know why. 40 is super low around town, but there are a lot of driving variables.
    set it and forget it on the highway removes some of those
     
  20. Buggs1a

    Buggs1a Junior Member

    Joined:
    May 10, 2025
    71
    14
    0
    Location:
    USA
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I go 55 mph on i5 north and south from Burien wa to federal way. And back home. Then some stop and go the rest of the way but cruise still a lot of the way around 35 mph. Or coasting a bit.

    in city is to me just not on freeway around my place. Not sure if city or not. There’s a lot of lights. So my assumption is stopping then accelerating is why mpg is so bad for me and not being able to use cc. I don’t push much on the pedal still. Not freeway speed 25-35. If I can set cruise I will at 28 or 30-35.

    Go from my place to Safeway. Little less than 2 mile maybe. Under 40 mpg both ways. Or I’m on the freeway mostly from my place to my sisters/parents. Every place close to me I’d go is less then 10 minute drive with good traffic.