G37 Transmission Issues with 4th -> 3rd Downshift
#108
Got the transmission on my G37S reprogrammed today. Honestly, I don't notice any difference. The two problems that stick out are the downshift/acceleration lag when fully depressing the gas pedal at highway speeds and after releasing the pedal, it seems to stick in 4th/5th gear (between 4,500 and 5,500 RPM) before dropping back down into 7th gear.
#110
Thanks for the tip on this. I just got my G37 sedan last weekend and was wondering about this. My wife has an EX and it runs very smooth. It doesn't have the 7 speed transmission but it is an Ininfinti none the less. I have the TSB in hand and an appointment on Saturday.
#111
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He showed me with his laptop plugged in that the only update that my car could take was the ECM flare update. He said my TCM version was higher than the one with the TCM downshift update. I was surprised by this since I bought my car in May so I had him call the home office tech to confirm. He said it just reduces engine breaking, but it's still there. When the ECM was finished, the system said I was fully up-to-date. He put a report into "fix" saying that I still had the symptom, so who knows?
The result: the down-shift problem got improved pretty good, but the engine braking problem only improved some, and I still felt it. ENgine braking problem didn't quite go away.
In contrast, when I had my car in service, they gave me a 2008 G35 as a loaner car. Guess what? I loved the drive of that car. It is truly a smooth/silky drive, exactly the way I expected to drive the car. It had zero down-shift problem, and zero engine-breaking problem, with its 5-speed AT (instead of our 7-speed AT). I was hoping, I'd drive my G37, as silky smooth as the loaner car. But I was dis-appointed that the problem still didn't got fixed completely.
I don't know what exactly done to my car. Then I went on vacation, just got back yesterday.
I'm going to try to contact Infiniti again to see what was done and see if they can take a look at it again. I'll give another update later...
#113
I got TCM updated, but still dis-appointed. Here is the story: I brought my car in on Fri 7/10/09. Service Adviser refused to put my request to obtain this TSB update, but on service description it said a brief problem "hard down shift from 4th to 3rd". When I got my car back, it also had a brief description: hard down shift confirmed and re-programmed TCM, without mentioning anything about if the mentioned TSB was applied or not, as though, they were somehow afraid to show that being the service they did. I turned in my car 8:30am, and the car was finally finished at 6:15pm (they closed at 6pm). Thus I had little time for any good explaination of what really was done. Then in next few days I went on vacation until yesterday.
The result: the down-shift problem got improved pretty good, but the engine braking problem only improved some, and I still felt it. ENgine braking problem didn't quite go away.
In contrast, when I had my car in service, they gave me a 2008 G35 as a loaner car. Guess what? I loved the drive of that car. It is truly a smooth/silky drive, exactly the way I expected to drive the car. It had zero down-shift problem, and zero engine-breaking problem, with its 5-speed AT (instead of our 7-speed AT). I was hoping, I'd drive my G37, as silky smooth as the loaner car. But I was dis-appointed that the problem still didn't got fixed completely.
I don't know what exactly done to my car. Then I went on vacation, just got back yesterday.
I'm going to try to contact Infiniti again to see what was done and see if they can take a look at it again. I'll give another update later...
The result: the down-shift problem got improved pretty good, but the engine braking problem only improved some, and I still felt it. ENgine braking problem didn't quite go away.
In contrast, when I had my car in service, they gave me a 2008 G35 as a loaner car. Guess what? I loved the drive of that car. It is truly a smooth/silky drive, exactly the way I expected to drive the car. It had zero down-shift problem, and zero engine-breaking problem, with its 5-speed AT (instead of our 7-speed AT). I was hoping, I'd drive my G37, as silky smooth as the loaner car. But I was dis-appointed that the problem still didn't got fixed completely.
I don't know what exactly done to my car. Then I went on vacation, just got back yesterday.
I'm going to try to contact Infiniti again to see what was done and see if they can take a look at it again. I'll give another update later...
If you read my notes and others', this update does not fix every problem posters have encountered. The throttle lag is still there for me as well as a tendency to stick for a couple of seconds in 4th/5th gear at around 5-6k RPM after releasing the gas pedal before dropping into 7th.
Then there is the 'flare' issue as well. There most certainly are still some kinks to be worked out...
#116
Had the TSB done on July 3. My impressions after almost 3 weeks of driving and 2x 300+ mi roadtrips (again these are MY impressions and not speaking for the collective):
*rough downshift fixed;
*smooth shifting through all grears in all modes (silky smooth)
*serious bouts of either throttle lag or shift lag which I had not noticed before TSB
*decreased gas mileage (~1.2 mpg average)
The mileage issue I can live with as I still get better than 27 on the interstate and ~22 combined driving but clearly I've given up some mileage by (here's my assumption) leaving the throttle open slightly to smooth out the downshifts and reduce engine breaking issues.
However the throttle lag and/or shift lag concerns me greatly and is new for me since the reprog. I have noticed it 3 times. The first I was being cute and floored it from a 3 - 5 mph rolling start and the car did not respond at all (it felt like it was in 3rd gear or something) rather it just slowly climbed up to speed for a couple of seconds before dropping down into the right gear and taking off like a bat out of hell. It was a bit embarassing as it sounded like the car was flooding out before it kicked into lower gear. The other 2 times were when I was crusing the interstate and gave the car considerable gas to pull out and pass...again the car didn't downshift rather it felt like it "missed" even though the engine was purring smoothly and then finally started picking up speed gradually before dropping a couple of gears and taking off. That's a good way to get yourself killed at 75 mph. Am I the only one with this problem since the reprog? I can't tell if it is a throttle response issue or if it a transmission shift issue and unfortunately cannot duplicate the problem at will. It just kind of happens and now I spend more time looking for it to happen and less time enjoying the ride.
One final comment, my service documents do not mention an ECM program rather just the TCM re-program. You would think they would document something like that. I have heard people say it was prerequisite and others make no mention of it (like my dealer). The TSB makes no mention of an ECM re-program either.
*rough downshift fixed;
*smooth shifting through all grears in all modes (silky smooth)
*serious bouts of either throttle lag or shift lag which I had not noticed before TSB
*decreased gas mileage (~1.2 mpg average)
The mileage issue I can live with as I still get better than 27 on the interstate and ~22 combined driving but clearly I've given up some mileage by (here's my assumption) leaving the throttle open slightly to smooth out the downshifts and reduce engine breaking issues.
However the throttle lag and/or shift lag concerns me greatly and is new for me since the reprog. I have noticed it 3 times. The first I was being cute and floored it from a 3 - 5 mph rolling start and the car did not respond at all (it felt like it was in 3rd gear or something) rather it just slowly climbed up to speed for a couple of seconds before dropping down into the right gear and taking off like a bat out of hell. It was a bit embarassing as it sounded like the car was flooding out before it kicked into lower gear. The other 2 times were when I was crusing the interstate and gave the car considerable gas to pull out and pass...again the car didn't downshift rather it felt like it "missed" even though the engine was purring smoothly and then finally started picking up speed gradually before dropping a couple of gears and taking off. That's a good way to get yourself killed at 75 mph. Am I the only one with this problem since the reprog? I can't tell if it is a throttle response issue or if it a transmission shift issue and unfortunately cannot duplicate the problem at will. It just kind of happens and now I spend more time looking for it to happen and less time enjoying the ride.
One final comment, my service documents do not mention an ECM program rather just the TCM re-program. You would think they would document something like that. I have heard people say it was prerequisite and others make no mention of it (like my dealer). The TSB makes no mention of an ECM re-program either.
#117
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Not so Great
I took my Sedan in for the TCM update at Infiniti of Lisle. Thought it would be a trivial process, not so much.
My TCM module serial is within the range for the update, but was told that my trans already had the newest software.
They contacted Infiniti tech support, and now they are getting a new update supposedly specifically for my TCM. No ETA, but hopefully this will end well.
Brent
My TCM module serial is within the range for the update, but was told that my trans already had the newest software.
They contacted Infiniti tech support, and now they are getting a new update supposedly specifically for my TCM. No ETA, but hopefully this will end well.
Brent
#119
I took my G37 Journey (Made in Nov 2008) to a Beijing dealer for the TSB today. The Infiniti technicians plugged in the Consult III and told me that the TSB update was not applicable to my car, since they retrieved a TCM version number of 31039-3RX0E, which, according to them, is much newer than the 31039-3RX0C reported in this forum. I wonder if the guys know what they are doing and/or whether their Consult III is with the right software version. My questions are
(1) Does any of you know what happens if the Consult III itself is not updated?
(2) What is the date of manufacture of your vehicle?
(3) Is it possible that a G37 made in Nov 2008 already has the latest TCM firmware while the TSB was release in late June, over 6 months later?
Thanks a lot in advance.
(1) Does any of you know what happens if the Consult III itself is not updated?
(2) What is the date of manufacture of your vehicle?
(3) Is it possible that a G37 made in Nov 2008 already has the latest TCM firmware while the TSB was release in late June, over 6 months later?
Thanks a lot in advance.
#120
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I took my G37 Journey (Made in Nov 2008) to a Beijing dealer for the TSB today. The Infiniti technicians plugged in the Consult III and told me that the TSB update was not applicable to my car, since they retrieved a TCM version number of 31039-3RX0E, which, according to them, is much newer than the 31039-3RX0C reported in this forum. I wonder if the guys know what they are doing and/or whether their Consult III is with the right software version. My questions are
(1) Does any of you know what happens if the Consult III itself is not updated?
(2) What is the date of manufacture of your vehicle?
(3) Is it possible that a G37 made in Nov 2008 already has the latest TCM firmware while the TSB was release in late June, over 6 months later?
Thanks a lot in advance.
(1) Does any of you know what happens if the Consult III itself is not updated?
(2) What is the date of manufacture of your vehicle?
(3) Is it possible that a G37 made in Nov 2008 already has the latest TCM firmware while the TSB was release in late June, over 6 months later?
Thanks a lot in advance.