This is strange. I brought my 2009 G37X in to Infiniti today for an issue with the shift lock. Anyway, they gave me a loaner (2013 G37x w\ 3000 miles) and I was shocked. I reset the MPG to see if I my car gets the same MPG as a new one. On my same commute, where my car is 23.5-24.2, this one got 29.6. Really???

Were there any changes to the engine that would help that much with MPG? I know mine is 5 years old, but only has 47000 miles.
Optimistic Computer or is mine just a hog?

 

Different transmission gearing (5 speed vs 7 speed). Also the MPG computer isn't 100% accurate, there's a lot of room for error. If you figure it by calculating the number of miles driven / exact amount of fuel used you'll know for sure.

 

Mine has the 7sp

 

Shift lock? Ive been having trouble getting mine into gear and keep thinking it was just me.

 

Not strange at all.

I get very good MPG on mine.

Below shows my four fill ups from NJ to Florida. Not so great MPG doing short trips while in Florida and the four fill ups on the return to NJ



50 mile trip to work after fill up



Telcoman

 

Yep, sometimes it takes two or three times of releasing the brake and shifter to get it into gear. That and there is a slight buzz coming from the linkage @ 4000RPM or so.

 

@telcoman.

Maybe time for fresh plugs...

 

The 2008 G37 Coupe had the 5AT, then switched over to the 7AT in 2009 when the G37 Sedan came out, also with the new 7AT.

2008 was an odd year for the G-Thirty Something, that's for sure.

 

Thats not unheard of. I have gotten that out of cars here on the lot. Most I pushed a G was 30.2 on the high way dropping one off to a customer about 3 hours away. That was on the gauge, the math came out to like 29.1 or something.

 

LOL. I can get that if I reset the gauge going downhill with a good tailwind. LOL.

 

Not yet!
I changed them on my 06 G35 at 106.7k miles



Still have quite a ways to go.

Telcoman

 

I get about 24 on my 2013 and that's doing the math with a calculator after a fill up. the computer seems to give me about 3 more mph than I actually get.

 

2011, 21.7mpg 6 month average....im sure fluctuation is normal....no G is the same......wife has a Mazda 3 rated at 32mpg, best ever was 27.

P.S. She drives like grandma

 

I never get over 18

 

Still dont understand the 87 oct, no detonation? Timing?