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maximizing highway driving

Discussion in 'Gen 2 Prius Main Forum' started by srchf, Oct 17, 2005.

  1. srchf

    srchf New Member

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    I am driving about 70 miles one way and it's all highway driving. I ahve test driven the Civic and only mustered up about 38 MPG. I can't find a Prius to borrow to see how well the mileage would compare. I discovered in driving the Honda that I needed to have the RPM's under 3000 which meant about 72 MPH to even maintain about a 40 mpg light bar. my question is, Will the Prius be similar in useage? I'd like to buy one but if I can't get a better MPG response for highway running I can't justify the additional cost to that of a standard car that can achieve about 40 mpg. Also is it better to drive with or w/o cruise? I've seen some of the posts regarding driving tips but is there a listing of best practices for highway useage? thanks
     
  2. Maytrix

    Maytrix Member

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    Not knowing your driving conditions, it's hard to estimate. But here's what I can tell you.

    I have a 25 mile commute. Mostly highway miles, although half my time is spent back roads and the other half highway. I have found that on highway driving, I am able (in most cases) to sustain over 50mpg. I've even increased my MFD at times from 48 to over 53 while driving on the highway. The issue is how level is the highway you drive on? The majority of my highway driving has been fairly level (some hills of course, but not constantly).

    However, even on a trip I made to Vermont (fill up before leaving and filled up once I got back) I still got over 48mpg (I forget the number exactly, but it was over 48). My speed on the highway is as low as 65 and sometimes as high as 80. Usually I tend to stay closer to 70 though.

    Matt
     
  3. LaughingMan

    LaughingMan Active Member

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    if you could give us abetter idea of what your locale is, that would be helpful.

    Tough to say what highway mileage would be, but I have generally averaged in the 50s on the highways, but sometimes lower depending on the hillage.
     
  4. srchf

    srchf New Member

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  5. srchf

    srchf New Member

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    I'm driving from Mitchell, Sd to Sioux Falls, Sd. It's relatively flat, a few hills. The highway speed is 75 the entire way. I use the cruise on the current car and I seem to be averaging a few more mpg's than rated but would like to get alot more- hence the look towards the pruis
     
  6. taaustin

    taaustin New Member

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    How about this...

    I drove from Central Texas to the panhandle of Florida and back this weekend. I left on Thursday in the wee hours of the morning and came back on Sunday. (visiting family). I set the cruise at about 72mph and held it there much of the time. I spent an hour in traffic in Houston and an hour and a half stuck on I-10 north of New Orleans. Other than that the car cruised at about 72mph. For much of the daytime drive I had the AC on 78 degrees. My trip average was 51.2 mpg over 1864 miles, virtually ALL highway.

    Before I left I set my tire pressure at 42 psi in front and 40 psi in rear. I carry a $45 compressor, jump-start device that I got from Sam's Club so that I can adjust if needed, but I don't get anal about checking every day... I did check before beginning each half of this very long road trip.

    Is that enough info?

    Terry
     
  7. finman

    finman Senior Member

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    Mitchell to Sioux Falls? I've done that! About 47 MPG at 65 MPH. About 38 MPG in the dead of winter with a 40 MPH headwind, doing about 65 MPH.

    Across the whole state and back again, averaged 46 MPG with 70 MPH being average speed, light winds (a little rain even), 70 degrees and 2 passengers and luggage.

    Hope this helps! You can't go wrong with this great and versatile and low emission car.
     
  8. jeromep

    jeromep Member

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    75 mph is pretty darn fast. The Prius typically loose mpg as you get above 60 mph. Why, a combination of things, but mostly air resistance. The car is incredibly aerodynamic and has a very low Cd, however at those highway speeds, air resistance becomes a major factor.

    Topography is very important in trying to estimate FE on the highway. I'd estimate that on mostly flat land (even slight upward slope or downward slope will have significant effect) you probably will get around 50 mpg, but at 75 mph I suspect you will be getting in the high 40s. Not bad really.
     
  9. removeum

    removeum Member

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    B) srchf,

    I had the pleasure of traveling from Omaha, NE to Sacramento, CA and return in less than one week the first week of August. I used a total of 69.8 gallons of gas, traveled 3,222.9 miles and averaged 46.17 miles per gallon. Speed set at 75 mph, with A/C set at auto 74 degrees and saw the cars battery go down to one pink bar quite a few times too.
     
  10. Old n Bold

    Old n Bold New Member

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    Just returned home in Bellingham from a trip to south Seattle. While there, we took another couple to Kirkland then back to Federal Way. Nearly all the trip was on interstate and a lot was I-5 through the heart of Seattle. I kept about 4 mph over the speed limit most of the time to stay with traffic flow and didn't pay a lot of attention to the mfd (too busy watching the crazy traffic of Seattle). When out of the city, I had it on cruise most of the time.

    The total for the trip turned out to be 53.4 mpg. The car is 2005 #6 and has 10,000 mi. on it. Before leaving home, I checked the tires dead cold and adjsted them to 38F 36R. Used Shell gas for the trip and have just changed the oil. Using Mobile 1.

    P. S. Don't like driving in Seattle, but have to if I want to go to a Seahawks game.
     
  11. sotagear

    sotagear New Member

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    Just drove across the country in the last few weeks & passed through SD each way. I stayed at the speed limit or slightly above (75 to 80) most of the way & achieved an average of over 45mph for all 8300 miles of the 3 week trip. And that's mostly without cruise control & occasionally gunning it to pass big rigs & lots of elevation changes & occasionally windy conditions along the way. From the 12k I've put on the car the first 7 weeks I've owned it I can tell you that you'll probably get at least 42mph if you're at 75mph & paying attention to laying back on the accelerator pedal when you can. Of course that's at 60 to 80 degree temps. I haven't lived with it at colder temps yet & in No Cal, that only lasts about 2 months tops anyway, thankfully. I would imagine to expect reduced MPG in the colder months from what I've read here.
     
  12. Potential Buyer

    Potential Buyer New Member

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    When I rented a 2005 Civic Hybrid, I got between 23 and 37 mpg on the highway going 80 mph. Driving a Prius in the same manner, I got between 40 and 50 mpg with A/C off (but 31 mpg with it on, surprisingly). Even at 90 mph, the Prius continued to give me 40-45 mpg.

    I think the problem is partly attributed to the Civic Hybrid's weakness, which makes it struggle at highway speeds and thus use alot of gas. The reason I got 23 mpg with it was I was pushing fairly hard on the gas pedal and was maintaining a constant speed, but later I figured out I could release the pressure on the pedal and still maintain that same speed... so the engine is just really weak.

    From what I've read, the upcoming 2006 Civic Hybrid will fare much better than the previous generation, though I still expect the Prius to be the best (for city driving especially).
     
  13. Marlin

    Marlin New Member

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    I drove from Philadelphia to central Long Island recently and averaged 56.7 MPG. It was a total of 256 miles and was probably 95% highway driving. It was cool enough out that I didn't need air conditioning.

    In July, I drove from Philadelphia to South Carolina and back. Had my wife and daughter in the car and as much luggage as we could fit. Also had the air conditioner going strong cause it was hot as hell out. Averaged about 45 MPG on the way down and 48 on the way back.
     
  14. Catskillguy

    Catskillguy New Member

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    Another reason not to buy a rental.. As Jeff Foxworthy said, "Anything that's been ridden that hard by so many people, you don't want to stick your keys into". Of course, he was making an anology to something else
    ;)