Real World Highway MPG @ 75-85 MPH speeds?

Better product for commute speeds would be a regular Prius.My 2010 Prius 11 got 47 mpg on a 1300 mile trip to Erie,Pa from Dallas,Tx. Ran 75 to 85+ mph using cruise control as much as possible. most of the speed limits around here on the interstates and main highways are 70 t0 75 mph. most people are driving 5 t0 10 miles over the limits because they can get away with it. My Honda used to get 23 mpg on the same trip at the same speeds. No reason to drive under the speed limit for better mileage. My 2010 Prius handles the speed much better than my Honda CRV did. I run my tires with air pressure set to Factory specs for a comfortable ride and good handling. I get twice the mileage that I did with my Honda and a much more comfortable ride. I have had it up to 100MPH with no problems at all.

 

I typically get about mid-30's mpg whenever I drive my Prius (speeding on highway or local roads). My wife gets mid-40's to high-50's. I tend to be a bit more aggressive in driving mine....so a lot of it depends on driving style.

 

Ah, but what other vehicle out there can do as well at highway speeds as a c? Very, very few.

 

I took my c on a trip to Las Vegas from Colorado. Set the cruise at 85 for most of the trip to and from where the limit was posted at 75. Lots of uphills and down hills to knock down the MPG numbers on that route. I got a bit more than 38 mpg. I was hoping for 40+ but comparatively speaking, my 2000 Corolla 5-speed does about 34 driven the same way, so aerodynamics, low rolling resistance tires, and the battery regen on downhill grades must have made the difference.

 

I've noticed the Prius C is not very efficient on the hwy as well. I live in SoCal at sea level and would prefer to go slower, but 64mph is about as slow as I feel comfortable setting the cruise control at if traffic is moving unrestricted.

 

I just drove from Miami to Atlanta at 80mph. I got 38 mpg. If I slow down to 65 I can get about 50 mpg

 

Not really. Both my Nsx and S2000 only get 20mpg at 85-90mph. I like to drive fast and own a Prius and a plugin Prius. I enjoy getting 40mpg in my Prius at those speeds. I drive from Tampa to Miami all the time and it cost my practically nothing. I'm a car enthusiast and appreciate the efficiently of the Prius at all speeds. You don't have to drive slow to be a Prius owner.

 

If you are set on a Prius I'd get a 3rd gen or 4th gen for your type of driving. Diesels are maintenance nightmares and repairs are expensive.

 

Reasonable advice but the OP hasn't been here in 3 years.

 

I believe the target market for the Prius c is for city driving since it has a smaller ICE. Highway driving is for the Prius Liftback.

 

I get about 44mpg driving on "hilly" roads here in SE Texas at 70-75 mph

 

I took a photo of the last time I was out on freeway/interstate. I'm honestly surprised at the mpg. Cruising between 70-75 mph. Of course city traffic raised it a little

 

I drive pretty conservatively on the highway (heavy toll-police presence) and typically stay at or slightly below the speed limit. I've been able to average 56 mpg in the cold weather months and in the low 60s when the weather is warmer. The best I could ever achieve with my previous car, a 06 Acura RSX, was 41 mpg.

 

I don't remember on what page I read it, but the manual for my 2012 C has it written, "Do not drive at speeds in excess of 75mph." Might it be harmful to the ICE or battery?

 

I searched through the manual and it refers to driving with snow tires:

 

Last summer I drove round trip L.A. to Vegas. About 269 miles times two. I used eight gallons of gas. The data of mpg averaged 68. I drive very efficiently. The car performs. It did, anyway.

 

I LIVE at 80mph in my Prius-C. I average between 41 and 45 depending on whether i'm in the flats or in the foothills. Ignore the trolls... how can you say 45mpg @ 80mph isn't good?

 

we got 40 mpg measured at the pump, doing 70 mph from orlando to rocky mount, 620 miles, in our hycam.

 

It isn't how fast you go but how much burden you place on the gas pedal while going at the chosen rate of speed. Trust LRR tires to help. Then mileage goes up. Use the eco score screen. Forget eco mode. Aim for the leftmost measure practical to maintain on the graph. Use cruise control except upward grades.

 

That's all good advice! I never figured out how/when to use eco mode properly. Like I said I drive pretty fast, so maybe eco mode isn't for me anyway. I try to flip it on when I'm bogged by slow (-40mph) freeway commute traffic. But otherwise I've pretty much left it off (like I said, I don't really understand how to use it anyway). You also used the acronym LRR tires... I'm not familiar with that one. What does it mean? I'm rolling on 205/40/17's pumped up to 45psi (tire monitor HATES that...). But I figured less rolling resistance (even though it's a way bigger contact patch, probably). I'm also lowered 2.5" in the front and 3" in the back. I did everything I could think of to reduce air/friction drag except looking at the underside of the car to see where I could smooth stuff out.