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Discussion Starter #1 (Edited)
The Fuelly website has actual MPG data on 19 QX60 vehicles -- 8 gas, and 11 hybrid. Of these 19 vehicles, 16 have average MPGs based on 10 or more fills ups -- 5 gas and 11 hybrid QX60s. However, 1 of the 11 Hybrid QX60 with 10 or more fills looks to have bogus data.

Using only the average MPG data for the QX60 vehicles that have 10 or more fill ups, and ignoring the 1 hybrid with bogus data, I calculate the following:

GAS QX60 (5 vehicles):
Max Ave MPG = 21.0
Min Ave MPG = 17.4
Overall Average MPG = 19.1
Standard Dev = 1.6 MPG

Hybrid QX60 (10 vehicles):
Max Ave MPG = 25.2
Min Ave MPG = 19.0
Overall Average MPG = 21.1
Standard Dev =1.8 MPG

Based on this small sample size, the hybrid version of the QX60 gets 10.4% better fuel economy than the gas version.

Which only proves one thing, I am as big of a nerd as my wife claims.
 

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Discussion Starter #2 (Edited)
Here’s another look at the real world data in Fuelly. This time, I looked at the underlying data and threw out anything that looked questionable. For the Hybrid QX60, the MPG values are based on 199 fill ups (data points). For the Gas QX60, the MPG values are based on 108 fill ups (data points).

Hybrid QX60
Fill ups = 199
Miles Driven = 62,111.7
Gallons Consumed = 2,982.7
Max MPG = 27.7
Min MPG = 13.5
Ave MPG = 20.8
Std Dev = 2.4 MPG

Gas QX60
Fill ups = 108
Miles Driven = 30,654.1
Gallons Consumed = 1,588.2
Max MPG = 25.2
Min MPG = 14.3
Ave MPG = 19.3
Std Dev = 2.2 MPG
 

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Which only proves one thing, I am as big of a nerd as my wife claims. [/QUOTE]

Love the conclusion hahaha. Interesting to see on the 2nd post that the gas version is quite close to the hybrid mpg. Was hoping we would get more bang for your buck on the hybrid. =(
 

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Thanks for starting this... so any explanation as to why the std dev is worse when you throw out what your consider to be questionable data?

One of the hybrids is mine, by the way... I used fuelly when contemplating my purchase so I thought I'd "give back" for others. I'm averaging what you show, overall. Had a few low numbers when our was really hot and I say waiting for kids with the a/c cranking... I try to note such things to help explain what the numbers mean. And my high of over 26 mpg was when on a long trip all highway.
 

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Here’s another look at the real world data in Fuelly. This time, I looked at the underlying data and threw out anything that looked questionable. For the Hybrid QX60, the MPG values are based on 199 fill ups (data points). For the Gas QX60, the MPG values are based on 108 fill ups (data points).
I think you can safely include the Pathfinder numbers here, that will lower the SD significantly as there are a lot more Pathfinders out there.

They do not look too different either, pretty much in the same ballpark.

One of the '14 QX60s is mine and in line with Pathfinders. That said, I am genuinely intrigued by the +5 standard deviation mileage that some forum members seem to be reporting. I think member avishal is gettin 25-27 regularly. I have never seen anything approaching that.
 

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^ Ya thats me. 27mpg was I think mostly highway one fillup. But I just filled up again today and averaged 24mpg exactly. - 50% hwy and 50% city I would say
 

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Discussion Starter #9 (Edited)
Thanks for starting this... so any explanation as to why the std dev is worse when you throw out what your consider to be questionable data?


Short answer is because there are nearly twice as many data points (and vehicles) for the Hybrid. Each vehicle is unique, and is driven unique. For example, my Fuelly data contains the lowest MPG rating of all QX60s (13.5 MPG), and I have a Hybrid. That particular data point was due to my wife's driving for one week (69 miles total). She takes my youngest daughter to preschool everyday. She has to make two 6 mile round trips in heavy stop an go, neighborhood school traffic, with the A/C on. The first 3 miles are downhill (about a 600 foot elevation change), when the engine is cold and has to run to warm up. Then the next 3 mile are all up hill, 6-8% inclines -- it's a killer on MPG as the data shows. The gas version would get about 11-12 MPG in the same driving conditions. Another QX60 Hybrid driving long distance (all highway miles at a relatively constant speed with no stops) achieved 27.5 MPG off a tank. So those two valid data points represent a large swing on either side of the mean value that effects the sigma value. The extremes in the data weren't as large for the gas QX60s, as there were only 5 of them.


What the Feully data does show is that on average, the Hybrid gets about 10% better fuel economy (2 MPG) than the gas version.


Based on this data, the vast majority of gas QX60s should average somewhere between 17.1 - 21.5 MPG.


Whereas the vast majority of Hybrid QX60s should average somewhere between 18.4 - 23.2 MPG.
 

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Do you guys think that they could improve on the hybrid MPG's? Or could it say like this or close enough to it for the rest of it's production cycle?
 

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Discussion Starter #11
Do you guys think that they could improve on the hybrid MPG's? Or could it say like this or close enough to it for the rest of it's production cycle?
I believe the could by using an electric A\C compressor in place of the belt driven compressor used now to allow more "start stop" driving mode in city conditions. The current design uses electic assist when accelerating in city driving, but it rarely shuts the engine off with the A/C on. Turn the Climate system off and it's a complete different driving experience.... Much more Prius like.
 
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