joesg37xs

Hey guys I've got a 2012 G37xs coupe. I have been noticing some quirky shifting ever since I got my car this past January. Car now has about 5k on the odometer. What I am experiencing is rough shifts from 1st to 2nd, rough downshifts, and a whole lot of gear hunting. When I use manual mode I notice the shift lag and shifts feels a bit jerky. I have brought it to the dealer 7 times since I got the car and every time they look at me like I'm crazy and tell me there is nothing wrong. I am aware that the 2012 models have the updated transmission software and have read that they seem to drive a lot smoother but this just isn't the case for me at least.

Now I read some people have had success with Grounding Kits and with Hypertech on smoothing out these problems. I have also seen threads on GTM's valve body upgrade and torque converter. Do any of these mods help? Is there really anything I can to to make my car shift better?

Besides this herky jerky transmission I really like this car, it's rare and its cool and if I can somewhat fix these issues I wont be forced to go BMW or Audi when my lease is up. I want to keep my G!

ANMVQ

iTrader: (13)

Just search man, there a thread on here, Harsh shifting, There is a TSP for it and a reflash for the TCM,. Check in to that.

37hevn

iTrader: (1)

i noticed the same in a test drive so thats why i got a 5spd auto. the hunting for gears you describe is how i described it too. and i asked the salesman what was wrong and he said nothing so i drove a 5 and had no problem.

KAHBOOM

iTrader: (4)

https://www.myg37.com/forums/g37-sed...reprogram.html

I think it only applies to slightly older models though... Not sure about the 2012. I would think the new program would already be on that one.

However I hear there is a new TSB for the Ms for the 11-12 models so that one might also be applicable to the G

joesg37xs

Thanks guys yea I read that thread on the reprogram. My car is at the dealer right now so I called them to ask if they can apply ITB12-027, they soon called back and told me the update only applies to 2010 & 2011 models. I can't find the tsb for the M so if anyone knows the code that would be helpful.

XMMAN

Why not ask to drive a similar car at the dealership and see if the other car shifts the same way?

ANMVQ

iTrader: (13)

Becasue it does, The 7 SPD is terriable. My wife's 10, Hs had the reflash and drove good for 10 days.. . Now back to hunting and you can actual feel the TQ converter lock and umlock while you are driving. EX I will drive her car in M mode,. Go into 3rd gear, Get off the gas and the get back on it( Not hard) Just normal driving. The whole car will thud, Like it just shifted gears but still in thrid???? Does it all the time every gear( maybe no 1st-LOL). But will do it. SHe drives in D all the time and every time I'm in the car with her I can feel the tranny all over the place,. IMO they should have never made a 7 SPD auto, Really, 6 was enough, Now there are 8 SPD( Chrysler) Why for fuel saving. But the everyday drivability now SUX, My car NEVER sees D always manual.

2008G-Man

Here is the M TSB:

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.

Chris11LE

The old flash (ending in 75) or the new one (ending in 27)?

There was one released in mid-May.

DashKid

iTrader: (2)

I agree with you on this. Just drove a 2012 G sedan the other day cause le gf is in the market for a car. Test drove the 2012 G37s sedan and man still can't get over the fact that they have not gotten rid of the hard thunk those when trying to downshift. I asked the sales person what ecu update was on the car and he had no clue and told me I would have to ask the service department. So le gf said no to the sedan. Going to the audi dealer to test drive the s4, than probably to the Lexus dealer to test drive the IS 350.

IMO it looks like Nissan is still using the old ECU updates for the new 2012.

BLBncsu

On the wifes 2008 G35 (granted its a 5spd xmsn) we had the same issue. We continually documented it at the dealership anytime it was there just in case down the road it failed completely. Took techs out for drives multiple times and of course it was all "normal/its a sports car/it adapts to your style/blah blah" until a year ago finally got a decent tech who recognized the problem and replaced the valve body on the xmsn under warranty. Now its smooth as silk, like it should be on cars of this class. I'd keep working on the issue at the dealership and have them resolve it.
Don't trust auto's yet, its why I like the 3rd pedal.

ANMVQ

iTrader: (13)

Her car does all off that, ,

OPPS my car does the lag sometimes when coasting and the NO REV matching( Some times) , To.. NO reflash for me tho cause I'll lose my tune.. OH well .

ANMVQ

iTrader: (13)

Not sure we had it done like 4-5 months ago, I think Jan, Which would be the old one.

joesg37xs

Dealership said ITB12-027 does not apply to my car. I also printed out the bulletin for the M37 and they wouldn't even look at it. Infiniti needs to come out with an update for the 2012 models!

XMMAN

I wouldn't suggest talking about other car's problems and trying to say that its happening in your totally different vehicle. Go in and ask to speak with the Service manager. Explain to him that since you purchased the vehicle, you have noticed the transmissions has been acting up. Offer to take him for a ride in your vehicle and a similar equipped vehicle to show the difference. They are not going to do an absolute thing for you if you can not recreate the problem. Dealership service department's get paid by the manufacture to complete warranty work. If they do not have documented reason as to why they are doing a massive job, they will loose alot of money. If the Service Manager will not speak to you or treats you incorrectly, demand to speak with the General Manager or Dealer Principle/owner. Refuse to speak to a Sales Manager, General Sales Manager, or GM's Secretary. If you truly believe there is a problem with your car, then continue to push it and demand the best of the dealership. At the end if their best is not good enough you can call NNA/Infiniti to complain and hope they sort it out, go to another dealership, or choose to seek legal advice.

One thing I will tell you is never try to act smarter then the Service People. Don't talk about TSB's on other cars. Most service writers/techs are extremely prideful in their brand knowledge and don't like when someone comes in trying to insult it.

Good Luck!