My G's got 86k miles and i didnt know how slow my upshifts were until i drove an 2011 XS with 85k miles yet shifts much faster than mine. Drove a new Q40 that did the same thing. I already have a grounding kit installed but didnt notice too much of a difference. Should I do the transmission reprogram that Infiniti released for 09 g37's. If not what else could cause this and how can it be fixed.

 

There is two updates for the 7 speed and it will help the shifts. Not sure if the 09 is included in the TSB but check to make sure, I did it to mine and I noticed a difference

 

What's your typical type of driving? From and to work...freeway or back roads at slower speeds? New vehicles have computer to adapt to your driving style. If you're aggressive the computer sees that and memorizes that. If you're driving like granny and grandpa to the store it will memorize that as well. It's always good to be "hard" on the car every once and awhile so it doesn't lose that aggressive attitude to it. A few WOT runs on a safe road help.

 

You can reset computer so it will learn your driving habit. But drive it aggressively.

 

Full ATF change might help too..