When I haven't driven in a while and the car's been outside (mid 30's f), getting and going into first is fine, but going into second is either very stiff or it grinds. Sometimes it's either a small grinding noise and goes into gear, or recently won't let me move the shifter at all(maybe it's because it's a louder and harsher sounding than usual and I just instinctively put it into neutral/third)

My clutch pedal is to the floor.
It's not when releasing clutch, but when I try to put the shifter in second.
After it grinds, I can put it into neutral and then back to second without problems.
It stops after a few shift changes, or after driving for a bit.

Just wondering if it's a quick fix like getting fluids replaced, or something else is very wrong.

 

That sounds as though there is a problem with the synchromesh. The cold weather is apparently adding to the problem, but if it is the synchro, it will probably become worse.

--Spike

 

I read that it happens with bad synchros after it's warmed up because the fluids are warmed up and thinner? mine only occurs when it's cold and goes away after warming up.
After some googling, I guess another bad synchro symptom is trying to get into 2nd/1st gear unless completely stopped, or something similar?

 

^^ You could check this by replacing your transmission fluid. In fact, the 2006 350Z service manual calls for a transmission flush at 45K miles.

The dealership will charge $300- $400 for the service. You can do this yourself

If you do this, you need:
- 4 quarts of Nissan GL4 Manual Transmission Fluid (MTF)
-2 new gasket-crush washers (Part #11026-4N200).

--Spike

I still think it's the synchro.

 

Definitely the first member ever to experience this.
Where is David when you need him...

 

Yes... Where is David? --Spike

 

I have the same issue with a cd009 swap and red line mt-90..

 

Yup, do the new Nissan oil flush, helped mine a lot.

Secondly, don't try and bring it straight down from 1st to 2nd. It seems 2nd is not in that position, it's actually further to the right, closer to 4th than you think.

Try putting just your fingers round the front of the shifter and not holding it, so kin of just pulling it down, almost let it center as it comes out of 1st, just don't push it that way.

 

Could that be when I sometimes lazily shift into 2nd, it feels as if I hit a bump and my hand slips off and it goes into neutral and makes me look like an idiot while driving?

Also how hard is it to a trans oil replacement? Easy as changing the oil, or will there be more steps and things to watch for?

 

It's the same as engine oil. No oil filter to mess with but you have to use a pump to fill it. Use ramps, if you have them. Much easier that way. Car needs to be leveled.

- Take plug out at the top,
- Put pan under the bottom plug,
- Take bottom plug out,
- Let it run out (go drink a cup of coffee/glass of beer)
- Replace bottom plug (use new gasket)
- Use an oil pump (found at your local auto store) to fill from the top of the trany (make sure to get oil on your face, shirt, arms, and all over the floor)
- Once it fills to the brim and pours out, replace the top plug (use new gasket)
- Clean up and thank God you don't have to do this for at least another 2 years

You'll need 4 qts of gear oil. The tranny takes about 3.1, the rest goes on the floor.

 

Mine does this when cold. I usually double clutch 2nd gear the first couple times I use it. Once the tranny is warmed up a little it works just fine. I wouldn't loose any sleep over it. I've heard of s2000's doing the same thing.

 

Except that what you and CheekyChung describe should never happen. The symptoms you describe are not typical and require repair.

--Spike
___________________
EDIT: If it's just that you cannot easily shift in cold weather.... it's probably OK. But the OP claims not being able to shift at all, so that is something different.

 

What Spike said.


Trust me, get some Nissan GL4 in there, it's worth it.

Cheeky, stascom pretty much nailed it, it's worth doing any time, don't just throw any old oil in there though, you've got brass synchros and they don't like GL5.

And yes, the gate patern may be why you shift that way. I no longer have to double clutch and 2nd is no problem for me when stony cold in the winter, just remember not to pull down and left as well.