I'm on my second g35 now (07 g35x sedan, previously 04 coupe) and I'm noticing that this is a much higher revving engine/tranny setup. Cruising along the highway at 70 I'm just shy of 3 grand on the tac. Any idea on what gearing options I can use to lower this? I don't really drive this one for speed. I just love the ride and the interior and the looks I get when I pass sexy girls . But I would also love to not spend $65-70/week in gas. My coupe got way better mileage it seemed for my mostly freeway driving. I've done all the usual remedies for better gas mileage I'm aware of other than messing with the gearing setup. I know that the awd and extra weight play a factor into it, but surely running finding a gear ratio set up to run at lower rpm's would help.

Any and all feedback is much appreciated.

 

Well if you wanted to avoid the fuel cost why get a G, they're notorious for bad gas mileage haha.

Well the cheapest option you could probably do is swap out your 5th gear for a taller one, which wouldn't actually be cheap at all. I'm not sure how you would get that done actually, but I've heard from others on here that it's a possibility.

 

Gearing is not an option, its what built with the car. I supposed you can change the gearing in the rear diff. but I doubt you have much option there.

If you like the G but want better gas mileage, upgrade to a G37 with 7sp AT. It gets quote a bit better mpg on the freeway. otherwise, clean your TB, replace engine air filter, use quality gas, properly (slightly over) inflate your tires would help as well.

I have a 6MT and I got around 25-26 mpg on the freeway setting cruise control between 70 but under 75mph, 1 person, no AC.

I say the mpg is not that bad

 

Unless you REALLY wanted a G37 I wouldn't be so keen on upgrading to that. The mileage gain is probably all around a 2mpg difference, and with the savings you get from that it will be an insane amount of miles to pay off the investment of upgrading.

Also I've been able to get 26mpg when I drive up to my university, and that was with the AC on and going 70-75. You could definitely get higher than that if you go at the speed limit the whole way.

 

You could try to swap to an 09+ automatic rear diff, it has a 3.3 FD ratio. For first gen models all Automatics came with a 3.3FD and 6MT have a 3.5 FD. In 07-08 both 6MT and 5AT came with 3.7 FD rear diffs. This is why your RPMs are much higher on the interstate than they were with your 04. In 09 when the 7AT came out, automatic models reverted to the 3.3 FD ratio.

That 3.7 FD is also probably why the 07 sedans felt so darn fast, but guzzle that gas.