axxion89

Hello all, I have this odd occurrence with my transmission and wanted to get some feedback from you all. I purchased my 2010 G37X back in March and had the issue that most everyone had with the programming of the ECU. I had the TSB done and it fixed all issues except for 1. When my transmission is cold (sitting overnight or in the parking lot during work) regardless of outside temperature, my RPM will drop by abut 300 RPM as it accelerates in 3rd gear. The RPM drop is also felt with an abrupt jerk / clunk that shakes the car and a sensation of power loss. This issue is worse in wet / rainy weather as well. Here are 2 videos I have to show the RPM drop:

https://www.youtube.com/watch?v=R9XN...ature=youtu.be

https://www.youtube.com/watch?v=xZoC...ature=youtu.be

I've taken it to the dealer and we have replicated the issue but they have said they have never seen it before and don't know what to do. They say its the torque converter locking and is normal up BUT once the transmission is warmed up, this stops happening. I contacted Consumer Affairs and they said the dealer told them its normal and I could not "replicate a problem" (different than what they told me) and I was suggested to take it to another dealer. The nearest dealer to me is 30 minutes without traffic and in CT, traffic will make it an hour drive so I don't want to go out of my way before seeing if other cars do this as well. (I did test drive other cars without issue).

My question to you all is have you noticed this issue with your G's or heard of this? I looked on here but nobody has reported a similar issue. Would be interested to see if anyone on here can replicate this or have any insight. Simplest way to try and replicate is to drive your car under normal acceleration where shifts are occurring around 2500-3000RPM and see if the RPM dips in 3rd gear. You can put the car into Manual mode to confirm because this isn't a gear shift and only occurs in 3rd gear (can occur at different RPM's under 3000 too).

Serpens

Mine does that.

EDIT: Honestly I've stopped worrying about the odd torque converter behavior on this car. After all the searching I've done I've seen one transmission replacement on someone's car that actually concerned me. That being said, Infiniti/JATCO could've designed this transmission better.

PerDiem

I have experienced the same sensation as you have described. The car would shift into third, and while acceleration continues, it seems to do a "mini" shift (your described RPM drop) before shifting further up the gears.

I believe the tech at the dealership may be correct on this account as our torque converters have different levels of "lock" at different speeds and gears (others on this forum please chime in if I've mistaken). This does seems to be more pronounced after a cold start, and gradually goes away as the car works up to operating temp.

At the same time, you may notice that the car seems to accelerate more slowly from a complete stop as compared to other cars you've driven in the past (at least I've noticed), and this can also be attributed to the "semi-locked" state of the torque converter.

conkus805

iTrader: (1)

I think it's pretty normal for our cars to do this while cold, as mine does it too. I find if I let my car warm up a little longer than I normally would, about 5 mins, the issue is less pronounced. Especially on cold mornings.

axxion89

Thanks for the feedback. My main concern was that this could be a symptom of a developing problem so its good to know that others are experiencing the same.

WannabeSport

iTrader: (3)

My POS does this as well.. This is actually one of the biggest things that annoys me because when Im getting on it but not flooring it, it does this then its like, okay, now im out of power, so i put my foot down more and all of a sudden I am taking off like a rocket because the car decided to give me 2 gears. I literally scream at the car in frustration.

Almatti

That same condition can occur in the M37X too. Remember guys and Dolls, it's all about squeezing every MPG out of the car. The 7AT (as you folks know the threads on this forum) is quirky and should have been designed more like the 8AT in Audis. The comfort I find is that in my work I drive other vehicles including a 2012 or 2013 Ford Taurus with a 6AT. It's less quirky, but does exhibit some different experiences. One is that it settles in to a too high a gear while driving at steady highway speeds, requiring me to step on the throttle to maintain the speed more than would seem normal. Hope I'm explaining that correctly. With the M, while accelerating I notice that it shifts into too high a gear too soon, unless I'm really stepping on it. Then the tranny feels its bogging a little. Same thing was felt in the recent Q50 loaner I had. The use of multigeared ATs helps improve MPGs at the expense of performance. I have many times expressed my opinion on this forum in other threads, the 2007 G35X with a 5AT was the best performing car I've driven over the past 45 years: Responsive, non hesitant, almost instant head jerking acceleration (in fact htere was TSB issued to tune that down with a ECU reflash because of complaints that it was too aggressive), with excellent handling and steering.

WannabeSport

iTrader: (3)

I have been babysitting a 2012 Audi A7 for the past 3 days and I'll tell you what, the transmission in that car is PROOF a multigeared transmission is capable of being responsive while doing the job that was intended. That transmission is like butter, and always puts you in the gear that your looking for. I am blown away.

Then I get back in my G and want to club baby seals. Ugh.

VeXeD

How many months left on them G? Looking forward to missing your RANTS!

WannabeSport

iTrader: (3)

You got 8 more months of my bitching, then your all free! bahahahahaha

Twista

iTrader: (1)

I feel like this transmission is fine it just takes some getting use to. It does like to keep the Rpms low which is fine by me. It also likes to accelerate hard it doesn't want to be babied around the streets. Like it needs to see 3000rpm shifts to be smooth. Downshifting you need to gas it a little to get it to change then a little more gas to start moving to avoid the head jerk. It won't give u thr instant throttle needed for a quick lane change but if u need to do that u should be in ds mode

Serpens

This is the biggest thing for me. I didn't understand why it was winding out the engine so much but I realize the shifts are much smoother when it does.

PerDiem

I second the notion about smoother shifts near 3000 rpm. There's no lollygagging with the 7ATs.

Gabe Cady

Hello! I just came to revive the form for anyone of you use to this or whatever if you still have your G ect, I just got this issue and fixed it with new camshaft position sensors!! All good now! 😁 It will take a drive to readjust and then it will be non existent! It happened to me as I arrived to the shop I was getting it looked at again today after putting the new sensors in..this is a big win!