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7 Speed Automatic Transmission on g37x sedan

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Old 04-17-2009, 12:51 PM
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safin25
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Cool 7 Speed Automatic Transmission on g37x sedan

I recently drove this car, this car is great on the Highway however it drives like crap on the regular roads. The downshift is awful, as the car quickly slows down (felt as if the car was resisting from moving forward). Most of the time, I felt like was driving with a huge load in the back. However once I hit about 40 mph it was fine. I eventually was a bit annoyed and drove the car in a DS mode, the car responded much better. Not sure why the manufacturer would do this. Anyonelse feel this way? IS the g37 Sedan RW's the same.? Do you guys see a major difference when modifing the engine, with stillen exhausts!

Last edited by safin25; 04-17-2009 at 01:02 PM.
Old 04-17-2009, 01:00 PM
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emtrey
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are you driving in sport mode? I find if you "roll" slowly to a stoplight you can feel the downshifts. They really don't bother me as much as some of the comments I read here.

Mabe something is "right" with my car or "wrong" with my butt dyno.
Old 04-17-2009, 01:04 PM
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Keng
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The Gear Ratio has huge gap at low gear, thus the heavy engine braking.
Old 04-17-2009, 01:41 PM
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KLB
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I drive around 110 miles a day, both on the highway and in the city. I usually only feel the downshift like that if I am slowing down quickly.
Old 04-17-2009, 02:19 PM
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ghostfaced37
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Sounds like you were in the DS mode
Old 04-17-2009, 02:40 PM
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safin25
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With all said, I like the car! I may purchase one believe it or not! however I wanted to know if this is an on going problem with the g37's! and if any steps have been taken to fix it.!
Old 04-17-2009, 02:55 PM
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JohnEnglish
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Originally Posted by safin25
With all said, I like the car! I may purchase one believe it or not! however I wanted to know if this is an on going problem with the g37's! and if any steps have been taken to fix it.!
It's not a problem it's due to the gap in the gear ratio between 1st and 2nd.
Old 04-17-2009, 03:00 PM
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KAHBOOM
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I am hearing more and more complaints about this inthe 7ATs. I think its just the spacing of the gear ratios as well. Plus ther eis more lockup in the torque converter than with the 5ATs.
Old 04-17-2009, 04:21 PM
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w0ady
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i use the downshifting to engine brake regularly. no problems here.
Old 04-17-2009, 04:58 PM
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JohnEnglish
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Originally Posted by KAHBOOM
I am hearing more and more complaints about this inthe 7ATs. I think its just the spacing of the gear ratios as well. Plus ther eis more lockup in the torque converter than with the 5ATs.
My G37S coupe is a 5AT and my G37xS sedan is a 7AT. They honestly seem the same to me. The only difference I notice is at highway speeds the crusing RPM is lower by about 1000 RPM on the 7AT.

I've only noticed the 2 -> 1 downshift a couple of times on the 7AT. Until someone pointed it out here I wasn't even aware of it.
Old 04-17-2009, 07:29 PM
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brynomon
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I posted a similar complaint after driving home from work yesterday and I almost got rear ended a few times. I think a lot of it depends on the traffic but I do think the downshifting (regardless of gear ratio differences or shift points) it is too extreme and infiniti should correct it. The traffic on the way home today was a little bit different and I didn't notice it as much. DS mode actually makes the shifting more jerky in stop and go traffic. Manual mode helps considerably because i can keep the car in third gear more.

My problem is with downshifting to second gear from third. The drive was so much better today even in standard D mode. I can't help but think the computer learns from the driving. Yesterday was my first drive in bad chicago traffic. Today was the second. I will see how it goes the next time the cubs play on a work day (thats when Lake Shore Drive is packed) and average speed is 8mph. Then again yesterdays traffic was much worse today because there was 4 accidents within 20 miles on i55.

Last edited by brynomon; 04-17-2009 at 07:30 PM. Reason: Incorrect spelling of infiniti :)
Old 04-17-2009, 07:31 PM
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Keng
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Old 04-17-2009, 07:53 PM
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Silver37
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Originally Posted by brynomon
I posted a similar complaint after driving home from work yesterday and I almost got rear ended a few times. I think a lot of it depends on the traffic but I do think the downshifting (regardless of gear ratio differences or shift points) it is too extreme and infiniti should correct it. The traffic on the way home today was a little bit different and I didn't notice it as much. DS mode actually makes the shifting more jerky in stop and go traffic. Manual mode helps considerably because i can keep the car in third gear more.

My problem is with downshifting to second gear from third. The drive was so much better today even in standard D mode. I can't help but think the computer learns from the driving. Yesterday was my first drive in bad chicago traffic. Today was the second. I will see how it goes the next time the cubs play on a work day (thats when Lake Shore Drive is packed) and average speed is 8mph. Then again yesterdays traffic was much worse today because there was 4 accidents within 20 miles on i55.
I think mine is doing the same thing. What speed is it happening? Mine is around 22-23 mph, so I'm thinking it's a 3-2 shift. It isn't always noticeable, but very irritating when it shifts hard...especially when combined with the big brake package on mine.
Old 04-17-2009, 08:10 PM
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brynomon
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Originally Posted by Silver37
I think mine is doing the same thing. What speed is it happening? Mine is around 22-23 mph, so I'm thinking it's a 3-2 shift. It isn't always noticeable, but very irritating when it shifts hard...especially when combined with the big brake package on mine.
Thats right around the point for me. The shift is hard and then engine braking. Its not so much the point at which it changes gears but how it does it.
Old 04-19-2009, 01:36 PM
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Silver37
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Originally Posted by brynomon
Thats right around the point for me. The shift is hard and then engine braking. Its not so much the point at which it changes gears but how it does it.
I'm normally a very smooth driver, but find it almost impossible to modulate this situation at times. I'm hoping they'll figure out a tweak soon.


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