Hey all - I just picked up an '07 G35x about a month ago. It's been really cold here the last few days, like single digits, and I've noticed a couple times now then when I get on the interstate right after starting the car it will hold 4th gear and not shift to 5th for a few miles. I'm assuming (hoping) it does this to warm itself up more quickly. Is that true?

 

are you in DS or D? either way if you engage cruise control it should go to 5th

 

In D. It goes to fifth after a few miles, I'm just not sure if this is intentional behavior.

 

thats weird

 

I had rough gear changing a few days ago when it was below 0. After driving awhile, it comes back to normal. Just give your car enough warm up then see what happens.

 

In my past experience with Nissan products yes, this is normal. It serves to warm up the catalytic converter to reduce emissions.

 

this is normal. The fluid in the trans needs to warm up before the car shifts into 5th on the AT.

 

normal.

and, most likely, it is the torque converter not locking up that you are experiencing. it will not lock until the trans fluid reaches operating temp. this is for emissions. the engine and transmission are tuned to function most efficiently at normal operating temp. the rpms will drop down a few hundred when the torque converter locks into 1:1 mode. the slippage which occurs when the converter is not locked helps generate heat which helps things warm up faster.

or, it could just be staying in fourth gear with the converter unlocked ready to go into 5th. the programmers at different car makers do it slightly differently. my tundra truck does the same thing.