What happens if you drive in low gear with a eCVT on the highway?

[JTsyo]

My sister borrowed by Fusion Hybrid over the weekend and apparently drove 40 miles in low gear. When the returned it, the average fuel mileage for the tank dropped from 47.6 to 41.3. I was surprised by the drop since it does well on the highway too but figured she didn't baby it like I do to squeeze out all the gas mileage. She later told me that she had it on low gear for the first 40 miles. Are cars smart enough to adjust to being on the highway in low gear? I wouldn't think it would let you redline it, the tach doesn't even show a redline.

 

[DominionSeraph]

Low just looks to enable engine braking. Seems you can cruise in it just fine.

 

[ChronoReverse]

Hybrids have lower fuel mileage on highways and because the gas engine is fairly small, the mileage will quickly drop off a cliff after a certain speed point. 41.3 doesn't seem to far off when considering that.

 

[JTsyo]

Hybrids have lower fuel mileage on highways and because the gas engine is fairly small, the mileage will quickly drop off a cliff after a certain speed point. 41.3 doesn't seem to far off when considering that.

41.3 is what it dropped to from 47, soitmust have been a huge drop to drop that much over 40 miles when it all ready had 200 miles for the 47 average.

 

[LTC8K6]

41.3 is what it dropped to from 47, soitmust have been a huge drop to drop that much over 40 miles when it all ready had 200 miles for the 47 average.

Yes, if you drive around in a lower gear, or restrict your auto trans to it's lower gears, you will burn a lot more fuel.

Not sure why this is a mystery.

This is why you get more engine braking. You are in a lower gear than normal.

If I put my transmission in 3 instead of D(5), I will burn a lot more fuel, and get a lot more engine braking.

 

[DominionSeraph]

Yes, if you drive around in a lower gear, or restrict your auto trans to it's lower gears, you will burn a lot more fuel.

Not sure why this is a mystery.

This is why you get more engine braking. You are in a lower gear than normal.

If I put my transmission in 3 instead of D(5), I will burn a lot more fuel, and get a lot more engine braking.

The CVT Low doesn't restrict it to low gearing.

 

[LTC8K6]

The CVT Low doesn't restrict it to low gearing.

No one said it did.

Looking around on the net, it seems like the engine also runs more often in "L".

 

[LTC8K6]

Low Gear:
Low gear (position L) is
designed to mimic the enhanced engine
braking available in non-hybrid vehicles.
Low gear will produce high engine speeds
to provide necessary engine braking. This
is normal and will not damage your vehicle.
In low gear, the gas engine will remain on
more often than in position D.

 

[SearchMaster]

I'm sure it's a combination of the engine running more and a different driver. My wife can drop my MPG by 5 just by borrowing it for a short trip. She has no concept of driving efficiently and your sister probably doesn't either.

Your MPG was probably closer to 40 when you first got the car and it took a while for you to train yourself to get closer to 50.

 

[Sheep221]

Lower gears always consume more, the lower gears are also meant to be used only in their respective speed range. Driving constantly on highway with low gear not just increase your MPG but considerably increase the wear of engine.

 

[LTC8K6]

Lower gears always consume more, the lower gears are also meant to be used only in their respective speed range. Driving constantly on highway with low gear not just increase your MPG but considerably increase the wear of engine.

The eCVT isn't actually using any lower "gears" when you put it in L...

It is mimicking some aspects of a traditional transmission with programming, so there really is no extra wear.

The effect on mileage is pretty much the same, though.