I drive a 2003 Infiniti G35 Sedan. I love the car, it’s comfortable, handles well, and is fast by 4 door standards. I had it for over 2 years before deciding to use the manumatic transmission option, and after several months of almost exclusively using the user-controlled option, I’ve gotten a pretty good idea of fuel consumption.
First, the car in question (5 SPD AT) doesn’t get the gas mileage numbers that I had hoped, likely because I live in a congested college town and rarely drive more than a mile at a time. The first few years of ownership I drove the G exclusively in automatic mode and averaged 16-17 mpg, as compared to the EPA estimated 19 mpg.
On a recent tank of fuel, I used manual mode exclusively, driving like a normal person. I would accelerate quickly when necessary but rarely exceeded 3,500 rpm. I got down to an eighth of a tank and decided to refill. Can you guess what the magic number was?
12.8 mpg. Ferrari bad, and this was shifting quickly and spending lots of time in 4th gear at 30 mph. It made me curious about what would happen if I drove like a jackass; so I did just that.
I spent the tank revving high in 1st and 2nd gear and downshifting early. I enjoyed hearing the engine soar above 4000 rpm. People likely thought I was going a lot faster than I was despite never exceeding 50 mph, and you know what my fuel economy was?
10.8 mpg. Keep in mind this is a Japanese V6 sedan. I know, it’s really bad. And expensive. Safe to say this is a one-time experiment, but it leaves the question, why use the manual option?
I originally thought it was faster, but with the quick 5 SPD AT it’s not, and it’s definitely not more fuel efficient. Maybe you want to sound like you’re going fast in 2nd gear without actually going fast. I don’t know how you drive so give it a try, just don’t come complaining to me when your Toyota Corolla starts guzzling gas like a pickup truck.