I have a 2007 g35x and been experiencing a rough shift between what I assume are 2nd and 3rd gear for about a year. Basically at light throttle, it will shift to second fine, then when it shifts again to 3rd gear after about a second the acceleration stops and rpm drop as if it coming out of gear, followed by a hard shaft before regular acceleration resumes. The dealer tried to reprogram about a year ago and it seemed to help a bit, but its come back and become worse.

Now in the past couple weeks at low speeds and light throttle (15-30 mph), similar to what you might experience driving on I-95 in traffic, sometimes I am occasionally getting a rough shift that shakes/vibrates the car, like a pulse/shudder type feeling for a second or two. I am confused as to why it still seems to shift smooth and quickly under load and heavier throttle. I would have thought if something was broken it would slip more under load. Any one have any insight on what it could be before I bring it into the dealer. Also I verified I am not crazy as 2 others have noticed it as well while driving with me. It is more common to feel it if I let off the gas as I approach a curve or slow traffic, then lightly re-apply gas to go a bit faster.

 

Same here. In my coupe if you leave your hand on the a/t **** you can feel it vibrating a lot when the car seems to shudder.

 

odd issue sorry to hear that... I don't assume it could be anything else except the transmission. I'm assuming your powertrain warranty is expired? At first when I read "shudder" I thought of spark plugs but that normally happens when you start accelerating in first gear. This seems like a possible vdc issue or the tranny is slipping.

 

I had the "shudder" at low rpms, technician swore it was the valve body so he replaced it twice. They never found the issue, I just lived with it for 3 years.

 

These cars have the 40 MPH shutter..mine starts at about 47-42 MPH

But yours is too low of a MPH for that

 

I think it is the transmission, I am at 65k so I have 5K left on the warranty (or November). It seems to have gotten better the last couple days but it has been a lot warmer out (70s vs 40s and 50s). I still felt it a couple of times. I have poked around on a bunch of forums and it seems the issue can be as minor as a loose harness or the fluid going bad, or as major as blocked screens, bad solenoids or the torque converter. I am due for an oil change so I will see what they say and report back, I know my software was updated about a year ago so I don't thinks that is the issue.