Almatti

That's correct Malu, TC = Torque Converter, an integral part of the automatic transmission. The TCM , the Transmission Control Module - all electronic - works in concert with the ECU = Electronic Control Unit ("the Brains Behind The Outfit"....) So either the TC must be changed with a new design of course, and/or new software must be developed and applied that will alter the shift points and response of both the ECU and the TCM. But I'm certainly far from a auto engineer.....it's what I've learned. You need to keep in mind: Infiniti came up with this to Increase Mileage on the entire Fleet - that meets the US requirements of MPGs. Can they produce something that will correct these issue after the car has been put in service??? Maybe?? They better, b/c I am still seeking to trade mine in - on a lease for a 2008 M35X

TinsleyC

And your experience shouldn't change. If it does, please let us know.

I took my 09 in to get the tranny flash but they applied the old one, instead. I *think* I prefer less engine braking, but often times I do enjoy it. After reading all here maybe I should sit on my ITB09-32b flash for awhile before jumping for ITB10-075.

Do you know for sure which flash you have?

Dexter_Morgan

i took my 09x in for an oil change and asked them to check on doing the flash. They said it didn't apply at this time. Not sure why since it's on the list of those affected.
2009 G37x.

TinsleyC

That's pretty much what I got. I think the key is to specifically report the problem that's outlined in the ITB. They don't have to fix it unless there is a specific complaint.

G37beijing

Does anyone have the TCM firmware version after the reprogram?

wpmcnamara

No, I do not. I'm schedule to have the car in today to get the spoiler and splash guards installed. If I think about it, I'll have a chat with my service advisor and see what he can tell me.

--wpm

MaluG37

Almatti - I think I know what you mean by the lag, but does it really get any better? Did the 5sp AT not have any delay shifting into the right gear? This is my first "sporty" AT and not sure what to expect. Compared to a standard AT it seems to shift fine with the reprogram. I've also driven a 6sp manual so I know how shifting manually feels and both before and after the reprogram I'm not overly impressed, but there are some occassion when it reminds me of my 6sp. Yesterday I tried a number of times to slow down into a corner and hit the gas. As long as you don't go below 25mph through the corner the trans takes a moment to shift into gear and off I went. If you go below 25 then it needs two shifts which slows it down. I tried the same on the highway traveling at 70 mph...slowed to 45-50 then hit the gas. Depending on how hard you hit it it would shift once or twice. If it shifts twice there is more of a delay...but that makes sense, right? In general the harder you drive the car, the better prepared the transmission is for your sudden speed changes. That's my thought. I like the way the car drives after the reprogram, but still needs some work. The downshifts are still there when you drive it hard, but a lot less when you just want to cruise around or are in stop and go traffic. I like engine braking and used to do it alot using my previous 6sp, but prior to the reprogram the trans would downshift at the wrong time causing jerking shifts and would drive me crazy.

blnewt

iTrader: (13)

I owned an 07 w/ the 5at and now an 09 w/ 7at, the 5at was always where you wanted it to be, no hesitation, no clunky downshifts and always in the proper power point in the rpm range. The 5at was THE perfect transmission for this car, if they would have just added a steep overdrive 6th gear to this transmission it would have satisfied the mpg gains and still been a sport transmission. The current 7at is just one big compromise IMO. Sure you get a couple more mpg, but it's not really worth it looking back on how fine the 5at was

Marc Collins

One of the other elements that has to be remembered (aside from the too jumpy throttle mapping causing 90% of the problems--fixed by Snow Mode or the latest reflash) is the unusual gearing of this transmission.

Unlike most cars, where the higher gears are progessively spaced farther apart (larger rpm change between gears), the G's tranny is geared like a race car transmission with smaller spaces between the gears as you go up the range. Hence the often noted frustration or curiosity that there is such a small difference between 6th and 7th gears. This design results in more frequent situations where a change of two gears is required to respond to the driver's input (throttle) instead of one (as described in the second previous post). It takes longer/causes a delay in response for the tranny to drop two gears as compared to one...no question about it because it is just the mechanical reality.

I experience no significant or noticeable delay downshifting one gear in my G. If you drive in DS, chances are the car will rarely have to drop two gears. If you shift manually and anticipate the situation, same thing. If you are in D and poking along, or driving in too jerky a manner on and off the gas and brakes too heavily in stop and go traffic (90% of the drivers on the road in North America based on my observations) and then need to go in a manner that requires a two gear drop, you will get the "lag" talked about here.

I highly doubt it can ever be "fixed" because it is a result of the design of the drive train itself. The latest reflash just attempts to mitigate the overly-sensitive throttle mapping from exacerbating the situation for most drivers who drive in a non-smooth manner or who are stuck trying to keep with stop and go traffic where everyone else is driving in a non-smooth manner. It should help, but it won't eliminate the lag if you purposely set up a situation to cause a two gear drop.

It just reduces the number of times that happens by using a more linear throttle that allows the car to get moving with a single gear drop hopefully to the point that extra throttle is not applied after the initial launch because you are satisfied with the degree of forward motion. In other words, dropping from 5th to 4th, but feeling acceleration immediately will prevent you from jamming the pedal further down to cause a shift back to 3rd. Having less torque available in 4th, but having it "instantly" accelerates you at the same effective pace as experiencing a delay while you wait for 3rd gear, but then take off more quickly. You end up in the same place at the same time in both examples, but one was smoother and required one less gear change (down and then back up).

The problem really gets complicated when the overly sensitive throttle causes an unnecessary (if you end up in the same place in the same amount of time as per the example above) two gear drop, so the response is to get frustrated or worried (as the oncoming vehicle gets closer and closer while you are making a turn in front of them!!) and depress the throttle even more while the two gear drop is under execution. Then the tranny has to think about the prospect of dropping a third gear and likely causes even more lag. Then when you finally get in to a gear, the tranny is convinced you are at a race track because you applied so much throttle in a panicked manner (the speed of depressing the throttle is as or more important complared to how far down you press it for tranny shift electronics) that it may behave inappropriately to the other extreme (holding gears, delaying upshifts, etc.) for a few minutes. Then you think what a stupid car this is because it doesn't seem to respond appropriately to what you need and want.

If you always apply the throttle smoothly (regardless of how far you press it), 90% of the problems will be gone. It requires more skill to do that before the latest reflash because of the extemely non-linear throttle mapping, but it can be done.

Try a test:

Do a 20-60 or 20-80 run by slamming the throttle to the floor from 20 mph cruising speed and then run the same test taking a full 2 seconds to go evenly/smoothly from crusing throttle to full throttle. The timed result will be so close to the same it is immaterial. But one will likely feel laggy and annoying; the other will feel responsive and satisfying.

The new reflash is just simulating the latter scenario by forcing a more linear throttle mapping. If you slam the pedal to the floor, you will get the same result reagrdless of the shape of the throttle mapping curve. But in the 99.9% of the time you are not doing that, it should calm-down the transmission from over-reacting to driver input. The car will feel less responsive driving out of your driveway or taking off from a stop, but it is the kinesthetic equivalent of an optical illusion. The performance of the vehicle is still there and now easier to modulate.

Given that, I should be first in line to get it done, except thanks to others whinging about the higher than average amount of engine braking programmed in, they have severely reduced that in the process. Too bad--it is what helps make sure the car is most often in the right gear at the right time and allows it to be responsive more like a manual transmission-equipped car.

MaluG37

Well written Marc. I agree with most of what you wrote, except that I drive smooth and maybe it was me trying to baby the car too much since it was new that caused the transmission to feel worse than it really was. But there were many times when a vehicle in front of me slow down (sometimes abruptly as mentioned above) so before hitting the brakes I would roll off the throttle and depending on the speed the engine would begin to engine brake (usually severe enough to toss the passengers forward) which is understandable for a performance car. The car in front would turn out of the way and I would gradually press the accelerator to try to smoothly accelerate and the trans would either delay a shift by hanging onto that lower gear or abruptly shift into a gear which further added to the jerky feeling. After the reprogram it doesn't do that anymore, just sticks with the current gear or downshifts when appropriate. You’re right this car has been geared to race and those that have to deal with stop and go traffic suffer the most. When downshifting a manual vehicle I was able to keep things smooth and within the appropriate power band. This is a AT and there isn’t a way for it to anticipate the road ahead besides prior throttle and braking inputs so driving angry will reward you with crisp shifts, but driving economical usually results in jerky shifts and hesitation since the car was made to rip through the gears.

Almatti

My exact Feelings... I will add that driving our company car - a 2010 Ford Fusion SE with a 5 or 6 spped auto tranny , non shiftable (no Manual Mode), in NYC traffic today, I did feel some gear hunting - jerkiness too. Also, comparable to our cars, going into a turn, hitting the brakes then the gas, there was some laggin g too. This diffres from what i had mentioned in an earlier post. Today I was specifically concentrating on that type of drive. Hey, in NYC, there is no other way to drive except in T R A F F I C...

Almatti

Malu: I agree that Marc has submitted a fine "white paper" supplying great information. I think one thing may have been overlooked. The TCM can be reset and therfore change the 'adaptive Learning" of the TCM and i guess it's ECU inputs. So, Reset your system as others have described here (I think Fish was doing it more frequently in other posts here), Drive very agreesively for 100 miles or so, and see if that changes anything. I may try that too. But Marc' analysis on the lagging was very informative.

TinsleyC

But isn't the "learning" process continual? Are we saying the car "learns" over a set period of time and sticks with that?

I would think that i it is "learning" it would do so over a most recent tme window, and average it. In other words, driving hard for 100 miles may help the next 10-20, but after another 100, isn't the first 100 just fun and wasted gas?

joshkim

Hey guys.

first time poster on the forum. Just got the new 2011 G37xS 7AT. I have been experiencing similar things that people have posted on the forum about the transmission. I have only 700 miles on it and I'm wondering if I should wait a little longer for the car to "break in" or if it matters if I take it in for service.

Im getting mixed reviews here so i'm wondering if anyone with the 2011 who had the reflash done can comment

also, what do i say to the dealer if they tell me nothing is wrong with the tranny but I want them to do the reflash. I hear some people hearing from the dealership that there's no such thing. Will they get upset or annoyed at me to bring this up?

thanks

tharbemiko

iTrader: (1)

There is a high chance they'll be annoyed. I called my local dealership about the reflash and he said he was tired of people calling in requesting the reflash when there wasn't any problem with their transmissions in the first place :/. If you want to get the reflash, you have to demonstrate (with them in the car) the issue or else you won't get it.