G37S 7 speed automatic transmission feedback
08-08-2009, 12:06 AM
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G37S 7 speed automatic transmission feedback
I just purchased a new 2009 G37S coupe with 7 speed automatic transmission. I guess I didn't pay attention during the test drive, but after I purchased the vehicle and drove it home I have to say that the transmission is a tad annoying at times. I'm coming from a 5 speed AT 2005 G35 coupe, so maybe I'm not familiar with how a 7 speed works. My complaint is:
When in stop and go rush hour traffic, when I am doing 25 mph and then have to take my foot of the accelerator because traffic ahead has stopped, often the transmission will BRAKE the vehicle (almost as if I was in a manual transmission and was downshifting gears). In my old 2005, when I took my foot off the accelerator, the vehicle simply coasted, effortlessly, with no jerking, no interference. But the G37S definitely has the transmission interrupting the deceleration experience.
Is this normal for a G37 7 speed auto transmission?
Thanks.
Phil
When in stop and go rush hour traffic, when I am doing 25 mph and then have to take my foot of the accelerator because traffic ahead has stopped, often the transmission will BRAKE the vehicle (almost as if I was in a manual transmission and was downshifting gears). In my old 2005, when I took my foot off the accelerator, the vehicle simply coasted, effortlessly, with no jerking, no interference. But the G37S definitely has the transmission interrupting the deceleration experience.
Is this normal for a G37 7 speed auto transmission?
Thanks.
Phil
08-08-2009, 09:54 PM
#4
Yep... When I get a 7AT loaner- I absolutely LOVE the upshifts in MM. It's an improvement over the 5AT- more direct, more TC lockup. The automatic downshifts when coating to a stop, however, are very jerky. With that said, I prefer the 5AT for that reason alone. If the TSB fixes that issue the 7AT would be perfect.
08-09-2009, 03:53 PM
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The TSB fixes it. I just had it done the other day. They flashed the TSU and it shifts a lot smoother. No more hard downshifting. I also came from a 5 speed g35 and the g37 doesn't feel anything like my old car. I wish they left the 5 speed in these cars.
08-09-2009, 09:19 PM
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>> I also came from a 5 speed g35 and the g37 doesn't feel anything like my old
>> car. I wish they left the 5 speed in these cars.
Funny, I've actually been thinking that I should have purchased a 2008 for just this very reason. Although the G37 has more horsepower, I recall my G35 as being more peppy and responsive than this new G37.
>> car. I wish they left the 5 speed in these cars.
Funny, I've actually been thinking that I should have purchased a 2008 for just this very reason. Although the G37 has more horsepower, I recall my G35 as being more peppy and responsive than this new G37.
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08-11-2009, 11:15 PM
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When I took the vehicle in for servicing, and handed them a copy of the TSB, the service rep said it did not pertain to my vehicle, even though the 2009 G37S coupe 7A/T was right on the TSB in black and white. "It's not in our computer," was his response. He also stated that my TCM? (transmission control module) was "not flashable". IS THAT TRUE? When I went to pick up the vehicle 24 hours later, the rough downshift was still there. Clearly they did nothing to address my problem.
The way I recreate the problem is to get on an empty road, no cars in front or back, accelerate quickly to 40mph, then let my foot off the gas and let the car decelerate on its own. When the engine RPMs drop to 1400, the needle jumps to 1800 and the 3rd to 2nd downshift takes place, which you can feel as a change in vehicle momentum. Then as the vehicle speed continues to drop, the tach will once more reach 1200-1400 and lurch up 400 RPM, at which point the downshift from 2nd to 1st takes place. It is at this downshift that the momentum "lurch" is most noticeable.
Phil
The way I recreate the problem is to get on an empty road, no cars in front or back, accelerate quickly to 40mph, then let my foot off the gas and let the car decelerate on its own. When the engine RPMs drop to 1400, the needle jumps to 1800 and the 3rd to 2nd downshift takes place, which you can feel as a change in vehicle momentum. Then as the vehicle speed continues to drop, the tach will once more reach 1200-1400 and lurch up 400 RPM, at which point the downshift from 2nd to 1st takes place. It is at this downshift that the momentum "lurch" is most noticeable.
Phil
08-11-2009, 11:28 PM
#10
Not true the trans is flashable. Find the date your car was made (usually in the door jamb drivers side) and if it's made before June it should apply, then call infiniti consumer affairs and report that you are unhappy and the dealer will not applie the TSB or go to a dealer with actual knowledge.
08-12-2009, 12:15 AM
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>> Not true the trans is flashable.
Is it the TCM that needs to be flashed, or the ECU that needs to be reprogrammed? I've read the other thread many times, and I'm seeing reference to both.
Is it the TCM that needs to be flashed, or the ECU that needs to be reprogrammed? I've read the other thread many times, and I'm seeing reference to both.
08-12-2009, 11:25 AM
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Overall, i'm very upset with what they did under the hood with this car. The inside is beautiful, but the car doesn't drive like a sports car, it drives like a hummer.
