Engine, Drivetrain & Forced-Induction
Have Technical Questions or Done Modifications to the G37? Find out the answer in here!

G37 Transmission Issues with 4th -> 3rd Downshift

Old 06-30-2009, 12:35 PM
  #16  
djsk
Registered User
 
djsk's Avatar
 
Join Date: Jun 2009
Location: Bay Area, CA
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Thanks brynomon.

I still havent bought my car yet but I did feel the transmission problem when I test drove the car twice. I'm really glad they found a fix because this was the #1 reason why I was thinking twice about the car.

I still remember the salesperson that was in the car denying the huge jurks the car had when I was driving it. I kept doing it over and over again so she could feel it. But that %^@& kept saying "it feels ok to me! It's just a sports car, thats what its supposed to do!" And I kept saying, cmon!!! it feels like someone who sucks at manual downshifting driving in an automatic car!! What a B****!!!
Old 06-30-2009, 05:54 PM
  #17  
PeterUbers
Registered User
iTrader: (1)
 
PeterUbers's Avatar
 
Join Date: Sep 2003
Posts: 424
Likes: 0
Received 5 Likes on 5 Posts
You're makin' me jealous with the feedback bryn!! LOL

can't wait to get this applied.
Old 06-30-2009, 08:57 PM
  #18  
gugarci
Registered User
 
gugarci's Avatar
 
Join Date: Jul 2007
Location: Bergen County, NJ
Posts: 541
Received 4 Likes on 3 Posts
Originally Posted by brynomon
This morning I did more than spirited driving. I was running late so I really pushed her hard with switching between DS and D mode a few times. DS mode appears to perform better as well when going from 50-20 and then back up to 70. Then when the road opened up I had fun with only a couple of lane changes and quick decel's/accels topping out at around 120. It seems as if the transmission programming changes do in fact make the rest of the shifts better. The performance and driveability of this car now has me floored. I will be interested in other peoples opinions after this update...

I must say Fields Infiniti was awesome. They are interested in my feedback on this since I was the first customer with this update and it not only affects the G series but the M and FX's as well.
Thanks for the update. I'm still a long way from service but I'll get it done next time I go in.
Old 07-01-2009, 09:59 AM
  #19  
timcodon
Registered User
 
timcodon's Avatar
 
Join Date: May 2009
Location: Houston, TX
Posts: 24
Likes: 0
Received 0 Likes on 0 Posts
Smile

Originally Posted by brynomon
Everyone,

Post after post has been made on this forum regarding rough downshifts and unnecessary enginer braking with the 7AT. Months have gone on and Infiniti has finally released a TSB on this problem.

I just drove my g37xS home and the difference is amazing. I'm no longer preparing for enginer breaking and hard down shifts. The transmission is much better now. So much better I don't think any other tranny in this price range compares. Bravo Infiniti Bravo! and to all of you naysayers in other threads regarding this problem...HA!

The information is as follows:

TSB: ITB09-032
Classification: AT09-009
Release date: June 24, 2009

Applied Vehicles:

2009 G37 Sport Sedan (V36) 2WD and 4WD
2009 G37 Sport Coupe (V36) 2WD and 4WD
2009 FX35 (S51) 2WD
2009 FX35/50 (S51) AWD
2009 M35 (Y50) 2WD Only

Applied Transmission: 7AT ONLY

If you don't believe it... Go Here.http://www.imagedump.com/index.cgi?pick=get&tp=550499
GREAT News of the day. After 2 months of frustration, to the point, that I'm seriously thinking about trading it in to Lexus (some model). Infiniti mst have been listening, and/or monitoring this forum, particularly related to this ennoying transmission issue. It's my VERY FIRST luxury brand from the normal brand: Honda, Toyota, Mazda. And it let me down. Now I have 3200 miles on it, just had a oil change yesterday. This issue has reduced some what from when I got my car in 4/24/09, but the roughness is still there. In addition, I'm not a sport car driver. All my prev cars have been family car & SUVs, so I'm probbaly will never completely "get used" to this current roughness, and seriously thinking to lose money and to trade it to otehr luxury brands...

This info is AWESOME. I just called Southest Infiniti in Houston to get this TSB software update done. My appmt is 7/11. I am cautuously optimistic that the sw update will correct the issue, or at least, get most of the ennoying thngs out of my system (rough down shifting & applying engine braking).

Brynomon, I thank you for your update info. Timcodon.
Old 07-01-2009, 11:01 AM
  #20  
brynomon
Registered User
Thread Starter
 
brynomon's Avatar
 
Join Date: Apr 2009
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
It's my pleasure to help out. I was at the same place that you were Tim. I know for a fact that Infiniti was watching this forum. The dealership was following this forum after I brought it to their attention. When I picked up my car the paperwork included print outs from the forum. Hell they even let me copy the first TSB info page so I could post it for everyone.

Don't be skeptical of this update. Embrace it, but if your unsure ask if they can revert to the original TCM if you don't like it but I will bet that you'll love it and find your car to be better than ever. Remember the TSB crosses several Infiniti model's.

Have a question...

How many of you ex manual tranny guys drive with your right hand on the shifter? Well I do. Up until the update I noticed the shifter to jerk at times during the downshifts etc.. This is also now gone. I do think this bad programming was hurting the trannie hardware.

Bryan
Old 07-01-2009, 11:19 AM
  #21  
Alex57r
Registered User
 
Alex57r's Avatar
 
Join Date: Apr 2009
Location: NYC
Posts: 523
Likes: 0
Received 1 Like on 1 Post
Hey Bryan, I do feel the shifter move like as if the motor and trans are rocking a little on the mounts and I do get rough downshifts sometimes(all the time in DS and very rarely in D), but they just don't bother me.

I don't get it, how can downshifts be this bothersome? And isnt engine breaking a good thing when slowing down? Or are some 09s just really bad and worse than others? i am not sure I would want my car to stop downshifting the way it does...
Old 07-01-2009, 02:02 PM
  #22  
brynomon
Registered User
Thread Starter
 
brynomon's Avatar
 
Join Date: Apr 2009
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Alex57r
Hey Bryan, I do feel the shifter move like as if the motor and trans are rocking a little on the mounts and I do get rough downshifts sometimes(all the time in DS and very rarely in D), but they just don't bother me.

I don't get it, how can downshifts be this bothersome? And isnt engine breaking a good thing when slowing down? Or are some 09s just really bad and worse than others? i am not sure I would want my car to stop downshifting the way it does...
I think a lot of it depends on the traffic you drive in and preference but the rough downshifting is not design. I get stuck in a lot of stop and go traffice with 15 -30mph speed changes. Seriously at times the shifting was downright dangerous with the combination of abrupt rough shifts with engine breaking that I have to brake in between gear changes but not during the shift. Then the person behind begins to take their foot off the brake and all of a sudden my car slows unexepectedly for them and they get pissed. It is downright dangerous and after a while in traffic like this i get fatigue. The only way I could make it safe was just keeping enough pressure on the brakes to have the brake light lit during the shift.

Imagine slow and go go traffic between 15-30 mph for 20 miles with bumper to bumper traffic. I did not spend 37k for added stress in my commute. I have to imagine how pissed off all of the fx50 owners were.
Old 07-01-2009, 05:29 PM
  #23  
krypt0n1te83
Registered User
 
krypt0n1te83's Avatar
 
Join Date: Jun 2009
Location: San Diego, CA
Posts: 47
Likes: 0
Received 0 Likes on 0 Posts
I called my local Infiniti dealership/service and they were not aware of this TSB. Do some dealership receives updates slower than others? They also said they wanted me to bring in my car to do full diagnosis before they can apply any TSB, is that true?
Old 07-01-2009, 06:11 PM
  #24  
brynomon
Registered User
Thread Starter
 
brynomon's Avatar
 
Join Date: Apr 2009
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by krypt0n1te83
I called my local Infiniti dealership/service and they were not aware of this TSB. Do some dealership receives updates slower than others? They also said they wanted me to bring in my car to do full diagnosis before they can apply any TSB, is that true?
I'm not sure if thats true but they are probably just trying to say that they won't just install a software update to install a software update. Some dealers are hesitant to discuss things like this over the phone as well. What I recommend doing is printing out the link of the TSB that I have and explain your symptoms to be the same.

Some dealerships are just not as cooperative as others. What can I say?
Old 07-02-2009, 11:35 AM
  #25  
HoustonG37
Registered User
 
HoustonG37's Avatar
 
Join Date: Apr 2009
Location: Houston
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
This is great news. However, it appears to apply only to the sport version???? I have just the normal 2009 G37 Journey (non-Sport version) and I feel this a lot. I have a call into West Houston Infiniti to see if I can benefit from it. I hope I can!! I'll let everyone know what they say.
Old 07-02-2009, 11:51 AM
  #26  
KLB
Registered User
 
KLB's Avatar
 
Join Date: Mar 2009
Location: Chicagoland
Posts: 700
Likes: 0
Received 0 Likes on 0 Posts
Sport only doesn't make sense. They all have the same transmission.
Old 07-02-2009, 12:11 PM
  #27  
Alex57r
Registered User
 
Alex57r's Avatar
 
Join Date: Apr 2009
Location: NYC
Posts: 523
Likes: 0
Received 1 Like on 1 Post
Originally Posted by brynomon
I think a lot of it depends on the traffic you drive in and preference but the rough downshifting is not design. I get stuck in a lot of stop and go traffice with 15 -30mph speed changes. Seriously at times the shifting was downright dangerous with the combination of abrupt rough shifts with engine breaking that I have to brake in between gear changes but not during the shift. Then the person behind begins to take their foot off the brake and all of a sudden my car slows unexepectedly for them and they get pissed. It is downright dangerous and after a while in traffic like this i get fatigue. The only way I could make it safe was just keeping enough pressure on the brakes to have the brake light lit during the shift.

Imagine slow and go go traffic between 15-30 mph for 20 miles with bumper to bumper traffic. I did not spend 37k for added stress in my commute. I have to imagine how pissed off all of the fx50 owners were.
I have spent hours in bumper to bumper traffic in the last two weeks, alot of it at 20mph or so, and my car just does not do what you are describing. Once in a while it will jerk on the downshift, but VERY rarely. Most of the time its very civil, at least in D mode.
Old 07-02-2009, 01:40 PM
  #28  
PeterUbers
Registered User
iTrader: (1)
 
PeterUbers's Avatar
 
Join Date: Sep 2003
Posts: 424
Likes: 0
Received 5 Likes on 5 Posts
I think everyone's sense of this 'issue' is very subjective, therefore how people describe it are going to vary a great deal -- from a downright safety hazard to a slight nuisance.

I'm in Alex57r's camp -- i barely notice it except for once in a while I feel that "perceptible" downshift 3->2. I can always feel the engine braking and actually don't mind that at all.

this is all in D mode -- i rarely, if ever, use DS mode.
Old 07-02-2009, 01:41 PM
  #29  
cflury
Registered User
 
cflury's Avatar
 
Join Date: May 2009
Location: Roswell, GA
Posts: 29
Likes: 0
Received 0 Likes on 0 Posts
Took mine in yesterday, drives like a totally different machine, more like my BMW drove. The shifts are way smoother now both up and down and the MPG's have improved by at least two MPG because the transmission will let you coast now rather than downshifting you as soon as you take your foot off the petal. I have not had a chance to throw it open in DS mode yet, looking forward to the weekend to do so.
Old 07-02-2009, 04:42 PM
  #30  
brynomon
Registered User
Thread Starter
 
brynomon's Avatar
 
Join Date: Apr 2009
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by cflury
Took mine in yesterday, drives like a totally different machine, more like my BMW drove. The shifts are way smoother now both up and down and the MPG's have improved by at least two MPG because the transmission will let you coast now rather than downshifting you as soon as you take your foot off the petal. I have not had a chance to throw it open in DS mode yet, looking forward to the weekend to do so.
Yes the difference is amazing and I noticed an improvement in my city or stop-go mpg as well.

Thread Tools
Search this Thread
Quick Reply: G37 Transmission Issues with 4th -> 3rd Downshift



All times are GMT -4. The time now is 02:54 PM.