MPG at Highway Speeds (65+)

Hello,

Just sold an 09 Jetta TDI, purchased a 2012 Prius II, picking it up next Monday.

What type of fuel economy should I expect at 65 MPH, flat surface cruising, no wind, 80 F ?

I have managed 50 MPG with Jetta under such conditions, but drop 4 mpg for every 5 mph increase, Just wondering how the Prius will compare.

Thanks,

Realistically, 45-50.

Sent from my MB860 using Tapatalk

Maybe even 55 mpg. See The most fuel-efficient cars and last page of http://www.consumersunion.org/Oct_CR_Fuel_Economy.pdf. Their test is at 65 mph.

In a GenIII I would say between 50mpg and 55mpg at 65mph. I can average 50mpg in my GenII at that speed and the GenIII is good for about 5mpg more when driven at highway speeds. Overinflated your tires and glide over overpasses and hills and you may see 55+.

I would say 45-50 mpg real milage.

The trip computer will say 5 mpg higher.

There aren't to many flat roads around here but I would say at an actual 65 MPH (indicated 67 or 68) I get around 45 to 48 MPG, which is an indicated 47 to 50 in my car. I have the 215 mm wide tires so my mileage is a bit lower than the 195 mm tires.

Prius may not be quite as good as your VW TDI for highway only but it should be a lot better at lower speeds. Plus regular costs less then diesel.

the key point is to drive with traffic,,
i have taken trips abt 6hrs in time and got upper 50's (55-59),, done this by staying with traffic and drafting. driving alone is much lower as has been stated,,
my 2yrs average is 55.7 with includes city ( where i can get 65-70 mpg any time),,, BTW she gets abt 48 ave.

I consistently get over 50 mpg actual in my Gen3 with 15 inch wheels if I maintain a relatively steady 65 mph for a long highway run. That allows for some traffic required speed changes.

That's with pretty ordinary driving, consistent but no hypermiling dodginess like drafting.

I drove 2100 miles for Thanksgiving last year on I-95 and kept up with traffic, sometimes going 70-75 mph, using CC too, and averaged 52 mpg for the whole trip. Weather was good but had to use heater to stay warm. I did take advantage of pulse/glide when I could but mostly kept my speeds steady.

Very high 40's to very low 50's is quite do-able. I don't have the benefit of flat & hot but got 50mpg round trip Philadelphia PA to Atlanta GA last month.

I just drove 470ish miles from LA to Woodland at 70mph with the cruise control on. The car is brand new; it only had 20miles on the ODO when I picked it up. Brand new tires and a newbie GenIII driver and I still pulled off 49mpg. I used no hypermiling techniques. I just drove it. The trip north usually nets me lower mpg than the trip south so I expect even better mpg once the car and tires break in.

From Bob Wilson's work:

As a worst case scenario, F8L and I made the trip down from Woodland to LA in my 2011 this morning. Ambient temp was 40F, 2 people, steady 75 mph, flat to downhill terrain, and Michelin Primacy MXV4 tires.

Result? 37 mpg calculated for a 300+ mi tank.

Mike didnt see the giant boat anchor I had tied to his bumper before we left my house.

I would get about 45-48 mpg goin 65-70 mph but I'm on wider tires.

Picked up my 2012 today and I can say that it does get better MPG's than the 09 TDI (apples to apples), around 2-3 mpg, but it’s early yet (break-in). It appears to be easier to "hypermile" it vs. the TDI. The TDI pretty much maxed out at 50 mpg, despite hypermiling efforts (I am an old Gen-I Insight "hypermiler" +70mpg). Has a very different feel about the Prius (vs. TDI) - softer, quieter ride. Much slower on the take-off though, but that's to be expected with the TDI's high torque character. Also had a slight performance tune, ran like a strong V6.

Love the Prius, it’s got more of a "high-tech" feel about it, more fun/interactive to drive, leaves the TDI feeling more like an "Eco tank". The TDI was a nice, solid car, but the high torque performance, and slight turbo-lag followed by fast spool-up on take-offs makes it more difficult to control in an efficient manner - TDI is more of a highway car. Really like the CVT, very smooth. The TDI’s DSG 6 transmission was a little “clunky” under hard acceleration.

Oh, and I don’t miss the diesel prices either, the increase cost reduced the net $/efficiency gains in half – 20% efficiency gain, 10% increase in fuel cost.

Congrats Hank! :rockon:

You should factor in the higher diesel service costs too. You can do a Prius synthetic oil change for <$30 if you purchase the oil/filter and change it yourself every 10K miles.

Must have been the extra weight you had on one leg of the trip.

Good point fotomoto. I did all the service myself, could not afford the car otherwise - VW service is very expensive. You almost need to be a foreign car mechanic to service one, relatively complicated, especially the transmission service. I manged for 100K miles, and don't miss it at all. The TDI is very German, both good and bad

Interstate hwy 5 from Longview Washington to Lacy Washington about 74 miles one way, did a round trip so 148 miles.

Date March 4, 2012, dry roads temps about 50 average. My wife
and I in the car some extra baggage about 450 lbs total with
both of us and bags.

Speeds 60 to 75 mph average about 68 mph. MPG gauge was between 54-56 mpg, calculated would be 51 or so. Reg
gas with 10% Ethanol. In summer the gauge would be reading
58 or so for about 55 mpg true.

Tires are Michelin Energy Savor with 57,000 miles on them
with 44 psi in all four.

Oil is Mobil One with only 4 quarts in the crackcase so
it is not over filled.