Which mode on Highway at 65

Use Eco mode.

 

In my v, at 61 MPH, Eco mode makes a difference in the summer, not so much otherwise.

Do not obstruct your fellow travelers, at 61 in a 55 I pass about as many as pass me.

Remember your goal is not high MPG, it is to use less gas. A longer route can have a higher MPG, yet use more gas.

 

I have to ask... Why would you be doing 61 in a 55 zone anyway?

 

flow of traffic I'd think, sometimes it can't be helped...

 

I am trying to minimize the risk of collision when passing, if I find the speed where the fewest people pass me, yet I pass the fewest people, that should be the lowest risk. Same reason I have my headlights on, minimize collisions.

 

Yep, fair enough. Equivalent in Australia of doing 100km/h in a 90 zone. You'd probably get a speeding ticket here for that (eventually)

 

The modes have no direct impact on fuel economy; they just make your gas pedal more or less responsive when you start pushing it down. Some people drive like they are wearing gumboots, others like they have bare feet. If you are a gumboot-footed kind of person, eco mode is meant to smooth out your heavy input to start with. If you want a quick response, power mode is widely thought to be best to start with. If you have pushed your pedal all the way down, all modes give the same result.

At any chosen speed, best economy is with a steady foot, on a flat road, speed constant. If the traffic is light enough, you can "drive with load" and try to keep the same pedal setting - you will slow down on hills, your average speed for your journey will reduce, your travel time will increase, and your fuel economy will improve. If you try to maintain speed whether in eco or power (or use cruise), your average speed will be higher, your time quicker, and your economy worse. Take your pick...

If you drive smoothly as above, if the traffic permits drop your speed a little - in steady flowing traffic, speed dictates economy more than anything else.

 

In addition, Eco mode 'relaxes' the A/C so it takes longer to adjust to changes, which helps in summer to lower the load on the big battery, and so the engine.

 

Power Mode does not have better pickup. It has better pickup per inch of pedal depression. When you put it to the floor, all modes are the same.

 

While I am paid shop to shop, all my clients PREFER to pay me for the time I am at their firm, the quickest route is the easiest to explain. "I billed you for an extra 1/2 hour because I chose to take this 45 MPH road rather than the main 55 MPH road" will not endear me to my clients.

Be aware that the EPA tests at 70 degrees ambient with an already warmed up engine. In real life it is often colder, windier, and my car has often sat for hours and so is 'cold'. You may find that in your life, you get better MPG at steady highway speeds than in stop and go in town. Try each route and see.

 

If you have the extra time it will take, and if the slower route is of similar length, yes. If it is much longer, then your fuel consumption may be greater, despite being at a more economical rate.
It's about the gallonage, not the mileage!

GT-I9300 ?

 

Well, what works for me to get great MPG in a highway is Cruise Control. I stay as much time as I can with CC. In a 65 MPH highway I set the CC at 70 MPH in that way I avoid the fine and I pass as many cars as other pass me. Even when passing cars I try to stay in CC, I just change the line and pass the slow car. I always have the car set in ECO mode. I only switch to Power if I want to cross a street and I feel that I need that extra power or just a more responsive car in that moment.

 

keep in mind that I live in Florida, a very flat place so CC just keep the speed without braking or accelerating too much.

 

That is how it works in the Mississippi delta as well, I gain 90 feet in 150 miles. Parts of downtown Seattle may gain 90 feet in a block.

 

In addition, you haven't noted your fuel consumption. Your highway trip used about 0.57 gallons; don't know the city distance from your post but you may have used MORE fuel on your city run seeing how much longer it took.
Speed is the problem on the highway, but it is usually the shortest distance, and speeds are reasonably constant; loss of momentum also kills your economy, so your city route didn't gain much.

GT-I9300 ?