I just got an 05 6MT sedan and lover it. It has now about 300 miles. I do notice that when I am almost coming to a coplete stop and put the car in first gear, I fell a vibration, no noise whatsoever though. The vibration is not felt if I put it inot first gear at a complete stop, but only from a slow roll. The vibration cannot be felt in any other gear besides first. Is this normal? Will it go away after the clutch differential and transmission breaks-in? TIA

 

Where do you feel the vibration?

 

I fell the vibration though the seat. It really cannot be felt through the shifter or steering wheel.

 

I don't feel that. I do notice it a bit tougher to get it in first without being at a stop.

 

I've noticed the same thing on and off since taking delivery in April. The vibration feels much bigger than I would expect for the light amount of force I'm putting on the shifter to try to get it into 1st gear. I just broke 3000 miles, and I suspect it's normal and will always be there.

Jim
'05 G35 Sedan 6MT, Garnet Fire/Graphite

 

I'm not sure I understand the situation. Are you experiencing the vibration under acceleration or at no throttle? I sometimes feel vibrations in the shifter and pedals but not the whole car, unless I did not give it enough gas when letting off the clutch. When that happens, the car kind of jerks around and not really vibrates. This is my first mt car so I am not always pulling off clean shifts. I pretty good these days but had a tough time when I first got the car. After I adjusted the clutch pedal, it became much easier.

I also notice it's a little tough putting it in 1st, even at a stop. It feels like there is something there to help prevent going to first gear on accident.

 

The situation I'm talking about is this: You're approaching a red light or stop sign. You're coasting or braking lightly and just about stopped, doing maybe 5MPH or less, so you have the clutch pressed all the way in so the engine doesn't stall. As you almost come to a complete stop the light turns green or you see the stop sign intersection is clear, so you try to put the shifter into 1st even though you're not dead stopped yet. The throttle is completely closed - no point in giving it throttle when it's not in gear yet. As you apply forward pressure on the shifter you feel this unexpected shuddering through the car whose magnitude is large enough that years of experience with mechanical things tells you couldn't be related to the light amount of pressure you're applying to the shifter to try to slide it into gear. However, after intermittently experiencing the same thing many times under the same circumstances you realize that trying to put the shifter into 1st is the cause of the shuddering, however unlikely it seems. We're not talking about a nasty grinding accompanied by appropriate grinding sounds. It's simply a vibration. And to be honest it's not an unnervingly large vibration, it's simply larger than one would expect based on the force being applied to the shifter. My G35 6MT has done it since day one, but it doesn't do it every time I get in those circumstances. I have not asked the dealer about it yet (closest one is 1 hour away) but am not overly concerned about it, especially now that I know at least someone else has experienced the same thing.

As far as getting it into 1st, I have on very rare occasions been sitting still at a red light for a while when it turns green and I try to get it into 1st but can't. I even try to apply a bit more force to the shifter than I would normally think necessary, but it still refuses to go into gear. I release the shifter so it fully falls back into neutral, let the clutch all the way out and then push it back in, and then the shifter slides right into 1st gear as easily as it should. I have no idea why this happens occasionally, but I've read other people on this forum mention the same thing, so I'm not too worried about it. I guess it's normal.

 

Try this. As you're coming to a slow roll and need first gear:

1) clutch in
2) move shifter to neutral
3) clutch out
4) clutch in
5) blip the throttle to 1500-2000
6) move the shifter into 1st
7) clutch out

You'd be surprised at how much easier and smoother it will be getting 1st.

 

My first car had a non-synchro first gear, so I learned to go through second to get to first in these barely moving situations. Having had a number of "well worn" manual transmissions after that, the habit has stuck. When the clutch is engaged but in neutral, the gears are spinning. Frequently with either a tight or worn transmission, it is hard for the first gear synchros to get things slowed down so that you can engage first. For me, putting it into second then moving to first seems to help.

 

too loud, you are exactly right in your description, but this cannot be normal. If I take it to the dealer, will they be able to fix it? If all models do not exhibit the same situation, I would think that ours has a problems??

 

I know exactly what you are feeling because my 05 did it at the beginning of its life. Now it has 4700 miles, it no longer shows this problem. It feels like the car is going to DIE (basically not letting the clutch out when comming to a stop feel). Might just need some break in miles for yours to go away as well.

 

Yes, I remembered doing this on my Nova, so i started doing it on the G, and it does go into first a lot easier.

 

Been there, felt that. But at 5600 miles, I think mine is still doing it (on occasion). I have changed my driving technique and rarely reenter first anymore, unless I have come to a complete stop.

To me, it feels like a driveline shudder, like the synchros are fighting to bring the driveline up to meshing speed. It is odd that its felt more in the seat than the gearshift, however.

 

sahigh, exactly it is felt through the seat! We should file a complaint with the NHTSA to see if Infiniti can come up with a fix. Has anyone been to the dealer with this issue and got it repaired?

 

That's exactly what I think is. You guys need to try the double clutch method I described. It makes like much easier for the syncros and entering a deep gear at speed.