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I've been searching high and low for this number. I've seen 14mpg being said in a couple of places. I saw 15mpg avg mileage on the test car I drove. But thats not a good indicator.
I also saw a 10.1 km/lit in a canadian review.
 

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I am getting anywhere between 19.1 and 22.3 MPG in the city! Very efficient for this size of vehicle. Of note, I am working on what I believe to be a small glitch in the Infiniti Cruise System. When you set your cruise and engage, the tachometer increases by 500 RPMs over what you can maintain with the gas pedal when not using the cruise control. I have never seen this in any vehicle I have owned so I am discussing this with InfinitiiUSA to see if there is a glitch i the system. Stay Tuned! Other than this minor issue - the car IS amazing. I have a fully loaded JX35 that is Midnight Garnet with Java interior. The electronics on the car are AMAZING! It has been worth every penny. I was really concerned with the engine being "detuned" over the FX35 (oh by the way I bought the FX35 2012 for my wife at the same time I bought the JX35 - she loves it as well) but I am very very pleased with the performance!
 

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I now have 4,000 miles on my AWD. I use 93 octane gas. With A/C always on, and transmission set to normal mode, I'm averaging about 19.1 in mixed driving. On a 1,600 mile road trip (800 miles of highway each way), I had two different highway MPG averages. That's because on the way up, I hadn't yet read the post on this forum from whoever it was [thanks!!] that discovered the manual shift up to sixth gear to defeat the extra RPM's on the cruise control. So, for the trip to start vacation, with 4 people and lots of stuff in the car, I got 22.5 MPG. On the way back home, with essentially the same load, but with the tranny in manual mode shifted to sixth gear, I got 23.5 MPG. Very hot weather both ways. Same route traveled. Same time(s) of day. Many thanks to whoever it was that posted that little trick first...I can't find it anymore, or else I'd call you by name! Next fill-up, I'm going to switch over to Sport Mode, and see what I average for the following week, for my regular, mixed driving. I love this car more and more everyday. So far, my impression is that it's just plain really-high-quality.
 

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Slap it over to manual mode, then up-shift to 6th. I take no credit for that. I'm not convinced it's a glitch, though. Now, I'm no engineer, but I suspect this might be on purpose...think about it this way, you've got dynamic cruise control, or whatever you call it, right? And the whole point of that is for the car to be able to slow down AND SPEED UP without driver inputs to the brake and throttle. I think maybe that extra 400-500 RPMs makes a lot of difference in terms of acceleration. Right about now you're scratching your head, and you're thinking, "What??? It's an automatic transmission...with a CVT, no less! Why should it matter what ratio is in play when I'm cruising? When it needs to accelerate, it should just do what it needs to do!" Well, I'm not so sure it does that. Here's an experiment I did: Normal mode, full auto, cruise set to 75. Creep up behind a car, wait for it to slow down about 10 MPH. Now, pull out into the passing lane and watch the tachometer. It doesn't really seem like it "down-shifts," or changes the ratio in any significant way. It just sort of speeds back up. Next, repeat the same experiment, except this time, with the tranny in manual mode, up-shifted to 6th. Pull out into the passing lane and watch the tachometer again...no down-shift. Just a much slower acceleration. Maybe there's some threshold, like if it's on a steep uphill or something. Anyway, I got the sense that the software is set up to try to stay in the cruising "gear." If that's true, the slightly higher ratio in auto mode may not be a mistake.
 

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Slap it over to manual mode, then up-shift to 6th. I take no credit for that. I'm not convinced it's a glitch, though. Now, I'm no engineer, but I suspect this might be on purpose...think about it this way, you've got dynamic cruise control, or whatever you call it, right? And the whole point of that is for the car to be able to slow down AND SPEED UP without driver inputs to the brake and throttle. I think maybe that extra 400-500 RPMs makes a lot of difference in terms of acceleration. Right about now you're scratching your head, and you're thinking, "What??? It's an automatic transmission...with a CVT, no less! Why should it matter what ratio is in play when I'm cruising? When it needs to accelerate, it should just do what it needs to do!" Well, I'm not so sure it does that. Here's an experiment I did: Normal mode, full auto, cruise set to 75. Creep up behind a car, wait for it to slow down about 10 MPH. Now, pull out into the passing lane and watch the tachometer. It doesn't really seem like it "down-shifts," or changes the ratio in any significant way. It just sort of speeds back up. Next, repeat the same experiment, except this time, with the tranny in manual mode, up-shifted to 6th. Pull out into the passing lane and watch the tachometer again...no down-shift. Just a much slower acceleration. Maybe there's some threshold, like if it's on a steep uphill or something. Anyway, I got the sense that the software is set up to try to stay in the cruising "gear." If that's true, the slightly higher ratio in auto mode may not be a mistake.
Good grief...I need to correct my own post. Turns out that slowing down 10 MPH will cause a "downshift." But 5 MPH didn't...at least not on a level straight-away. Aww, who knows? Maybe gazuccio is right...maye it is a glitch. Whatever the explanation, I'm fascinated. Still love this car.
 

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Nice to hear about higher mpg in manual shift mode. I'll have to try it out.
 

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JessyDog...Just throwing this thought you there. For arguments sake let's say cruising in manual at 70 MPH puts the RPM's at 2,000. And cruising at 70 MPH in Auto/normal mode the RPM's are at 2,500 RPM's. Could it be that the "gear" the engineers selected for '6th' is set lower than where the computer wants to put the car in auto mode? What you describe in your last post here is kinda how a regular hydraulic transmission operates. If you lock a car into it's "gear" and it's not allowed to downshift then it will accelerate slower. If you allow the tranny to resume the set speed in 'auto' mode it will get up to speed quicker. The slightly higher RPM's of Auto might just put the engine in a sweeter torque range to accelerate quicker. Great experiment....thanks a ton for sharing.
 

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It's not good to force the engine to move forward if it isn't in the torque range.
The most fuel efficient range for an engine is low rpm and high load. Least fuel efficient is high rpm and high load. Like a diesel engine. in a world of dsg's, lockup torque converters, manual transmissions and efficient cvt's I don't see how this damages or wears a drivetrain quicker. Back in the day when torque converters would not lock I would agree with this statement but maybe I don't fully understand what you are suggesting. Can you explain? Thanks.
 

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The ICC works fine in manual mode 6th gear for slowing the vehicle. If the car ahead speeds up and your acceleration in 6th is too slow for you, just throw it back into D. Once you are up to speed again, throw it back into 6M. Worked well for a 15 mile trip for me today! It takes some driver intelligence to assist the intelligent cruise control, but this will save gas in the long run.
 

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The most fuel efficient range for an engine is low rpm and high load. Least fuel efficient is high rpm and high load. Like a diesel engine. in a world of dsg's, lockup torque converters, manual transmissions and efficient cvt's I don't see how this damages or wears a drivetrain quicker. Back in the day when torque converters would not lock I would agree with this statement but maybe I don't fully understand what you are suggesting. Can you explain? Thanks.
I think what I was trying to say is.. Say for example you are going up a steep hill.. If you stay in 6th gear and bog the engine down to 1000rpm to save gas. It's not good for the car. You need to downshift to let the engine be in the right gearing to have the power to get up the hill. I know if you are trying to save gas you want to stay at lower rpms but don't take this to the extreme. If you need to get up and over something or pass someone you need to shift down. Or else we would all start in 6th gear and stay in 6th all day long.
 

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The ICC works fine in manual mode 6th gear for slowing the vehicle. If the car ahead speeds up and your acceleration in 6th is too slow for you, just throw it back into D. Once you are up to speed again, throw it back into 6M. Worked well for a 15 mile trip for me today! It takes some driver intelligence to assist the intelligent cruise control, but this will save gas in the long run.
Haha! "Driver intelligence..." Classic! My car doesn't have a gauge for that, but if it did, the needle would be pointing pretty close to "E!"
 

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Just under 1300 miles, standard mode, mostly city type, around town.. Getting 16.7 avg for the 6 fill-ups we have had. Highest was 17.9. JX is the wifes vehicle, but both of us have a lead foot.
 
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