Hey guys I have a 2011 G37x sedan and I recently brought my car in to my dealership for an oil change, and while I was there I told them about this rough/harsh downshifting I've been getting while coasting to a stop along with hesitation issues during acceleration and the service guy said OK this is a common problem with these cars I can reprogram the transmission and the ECU to stop that from happening and it will make the overall driving experience significantly smoother and more refined, so obviously I told him to proceed with it.

While they had my car I was looking up on here that the latest TSB on the Transmission software update is the 027A version which is suppose to be a major improvement in the overall transmission behavior, but when I got the car back they just gave me 2 printouts that showed as follows:

Transmission Re/programming:

Part number before reprog/programming = 31039-X351A
Part number after reprog/programming = 31039-X457C



Engine Re/programming:

Part number before reprog/programming = 23710-1NX6B
Part number after reprog/programming = 23710-1NX6D


Now I don't know what that really means, but what I'm trying to figure out is would these printouts indicate that they gave me the newest 027A update? Since I got the car back I noticed that the rough downshift during deceleration has been eliminated, their is less hesitation, and the overall driving experience definitely is smoother and more refined, so this would indicate to me that they did the 027A update, but I just wanted to make sure because I didn't see that 027A TSB code anywhere on any of the paperwork that they gave me. Can anyone help me figure this out? Thanks.

 

What I got for my coupe on 7/2/13 was;
ECM 23710-3WP5A
TCM 31039-X458C

Since you have a sedan and the numbers are close, you probably have the latest available upgrade. Much nicer to drive in D now, but I miss the old programming for DS.

 

Hi there,

the 027A update is the one performed on your car.

 

Ok thanks for letting me know, I just wanted to make sure that they gave me the newest transmission update because the 027A TSB wasn't specifically indicated on any of the paperwork they gave me. But I can definitely say I'm glad that I had this update done. I haven't noticed any more harsh downshifts during deceleration, the upshifts also feel smoother, and the transmission doesn't lurch or hesitate anymore either. Overall it's a smoother and more refined driving experience.

 

The 11's really seem to be problematic, of course I have one.

I think driving conditions make the issue worse. I drive in stop and go daily for 2 hours plus. I have noticed it worsen when outside of these conditions as a result of the stop and go.

I am wondering in this event would I even benefit from the re program

 

How is DS affected by the reprogram?

 

I took the advice from someone here about driving smoothly instead of trying to stab at the pedal to get it to downshift, and I have to say (even on my 2011) the transmission seems to work MUCH better using that method.

I *do* have the re-program but noticed the "aggressiveness" waned after 2 or 3 weeks. Driving it smoothly seems to make it downshift a bit faster (more like we all think it should), it seems to hold gears longer if it senses Im in a turn, etc. I also added an intake at the same time, so I dont know if the clean filters are affecting it (I doubt it, but maybe), but overall the car seems to act more predictable.

I havent tried DS after "smooth driving" in D for 2 weeks, but honestly it feels so much better now I dont really feel the need to do so.

 

Not as aggressive to downshift when on the brakes before entering a corner; more break pressure required to get a downshift, and it up-shifts quicker after exiting the corner. I used to be able to approach a corner stab the brake pedal, get 1-2 down-shifts and get back on the throttle and it would hold the lower gear until well past the corner or an up-shift at red line if that came up. Still happy with the upgrade since much more driving is done in "D".

 

Based on the significant improvement of my 2011 model after the transmission and ECM updates I would highly recommend it to you and to any other G37 owner who is experienced any of the undesirable transmission behavior. My 7AT operates noticeably smoother and more refined now. I also noticed more low-end power. And most importantly for me, I'm not getting the harsh downshift feeling when coasting to a stop anymore. Infiniti definitely did their homework with this 027A update. This is how the 7AT should have been programmed from the very beginning.

 

For the 3 1/2 years I've had my 2010 I constantly have read complaints on this forum concerning the auto transmission shifting problems.
During this time I have yet to have any problems.
Now I am down to 6 months until my warranty is over, so on one hand I'm wondering if I should bring it to the dealer and have the latest software flash done, while on the other hand I'm thinking that might be a big mistake since I have yet to experience any problems.
I don't like bringing my cars to the dealership for anything but warranty problems, so I do my own periodic maintenance.
Are there other owners out there that have no problems with their transmissions?
Tom

 

I also read about the problems and thought I did not have any, the trans just did something stupid occasionally. Then I had a 2012 loaner while my car was being serviced. I was five miles from the dealer when I called them and asked to check the car for a transmission TSB.
They plug the car in and only do it if needed. Well worth the time of sitting around the dealer a couple of hours.