Thank goodness..For us 2011-2012 M37/56 owners, the transmission update is available..I will be scheduling my appointment.

 

That's a good indication! I feel more confident now that they will have an update for MY09.

 

Argh! So where is it? The suspense is killing me!

 

Interesting thing I noticed is that my "miles left" indicator was actually RISING as I drove more today on a fresh tank of gas.

Im not saying its the most accurate thing in the world, but Ive never seen it rise throughout a day of driving.

 

Can MaluG37 or someone please post the pdf for ITB12-027

 

My 2010 G37 sedan (journey,prem) is in the dealer - Austin Infiniti today. I got a service loaner 2012 G37.

Boy, that car drove like a dream. The engine seemed a bit quieter and the transmission was butter smooth.

There is an isolated stretch of road with zero traffic and on my 2010, when floor the pedal a few things happen

1) The traction control light flashes (25k on the POS tire Goodyear RSA)
2) The transmission changes are a bit "violent". I can hear and feel the gears shifting. Going from 2nd to 3rd feels like a thud.

On the 2012
1) No traction light came on. (6k miles on Goodyear RSA)
2) Shifting was silky smooth!

I have the April 2011 update of the tranny (significantly better than stock)


Questions:
Is the fact that I feel the tranny change gears normal ? Remember this is full power 0-60.
Is there any engine or tranny changes between 2010 and 2012 ?
I am wondering if the TSB ITB12-027 will make any difference?

 

The new update will greatly improve the throttle and transmission. I feel a sporty auto will create firm shifts that you will feel. A smoother transmission won't be as sporty. The ITB12-027 update will feel smooth when cruising around town, but when you hit the gas the shifts are more direct but not clunky.

I don't have the entire TSB which is 10 pages...all I have is the first page with the description. I can post it if want it.

 

when my car was getting the update, i was given a ride home in a 2012. in the passenger seat, that car felt way better and smoother. I was sitting there thinking, wow, this is nice. i asked what year this was and the guy showed me the key tag and it said 2012.

 

For us M37 owners the TSP is ITB12-021.
Subject: SB 2011-2012 M37; Shift Responsiveness Issues
Summary of ITB12021:
IF YOU CONFIRM One or more of the following conditions: Harsher than expected down shifts when coasting to a stop.
Hesitation/lag when accelerating after coasting. Hesitation/lag or harsher than expected down shifts when coming
to a stop and accelerating again (rolling stop). Engine rev matching during moderate to heavy braking.
ACTION 1. Refer to step 6 in the SERVICE PROCEDURE to confirm this bulletin applies to the vehicle you are working on.
2. If this bulletin applies, reprogram the ECM and TCM. See this bulletin for further detail.

 

Got mine done today and drove about 50 miles combined city/hwy. Night and day difference. Besides shifting almost flawlessly, the increased torque from 2500-3500 RPMs feels huge. Had to get used to the increased responsiveness in 2nd and 3rd for a few miles, nice problem to have.

Also learned my dealer is an authorized performance dealer, whatever that means. But they are selling the Stillen supercharger which is so tempting now that it shifts so well. Published numbers on that are 115+ whp. So temped...

2011 G37x sedan.

 

thanks man, please post. i want to visit the dealer first on wednesday

 

Yes I was going to ask about MPG after the fix. Thanks for posting. Others?

 

I havent measured it yet either but I too think that the mileage has gone up. I usually have the mini display behind the wheel set on instant MPG. Before the update, it would mostly stay to the left of the "20". Since the update, it has been spending quite a bit more time to the right of the "20" .

 

Yes, I have seen this happen. Miles remaining is based on fuel economy which is worst during start up conditions and pulls down the average mpg. I've driven 40-50 miles on the highway and seen the same number of miles remaining as when I left home.

 

I planned to bring it with me today to scan, but I had to help my brother with a dead battery and forgot the paper at home.

All you need to do is tell them the problems:

- Harsh downshifts
- Lag/hesitation when accelerating
- Harsh downshifts and lag/hesitation when slowing down then accelerating.

If they can't figure it out then mention ITB12-027. I was in and out of the dealership in 30 minutes.