whenever i warm up the car, and drive for the first 5-10 mins i don't go into fourth gear. BTW i have a 2k2 auto. is it because the tranny fluid still needs to do some warming?? cuz i keep staying on third gear. i don't think there is any way to resolve this. but how about improvements?? hmm... like mobil or redling ATF? and plus since i live in IL, its gettin reallie cold over here. and its taking a longer time to get my fourth gear!!!

 

When the ATF is thick and cold, the torque converter won't lock up. Synthetic ATF (Amsoil, Redline or Mobil 1) can help alleviate this some because it will flow better at cold temperatures. I wouldn't expect it to go away totally though.

 

yes what he said

 

haha okay thanx for the input!!

 

Nissans have been doing this since the 1980's.
The ECU/TCU work together to control the transmission. If the engine water temp is not high enough, it will NOT shift into overdrive or TC lockup. Can't remember which one.
It has nothing to do with ATF viscosity or temp. Its all about emissions and quick warm up.

Best thing to do is start your car a few minutes before you leave for...... This way the engine has time to warm up. Also, avoid the highway until it is warm. The cold windchill will slow down the engine warmup which will exaggerate this issue.

 

ahh.. icic.. that makes more sense.. so basically it doesn't have to do anything with the ATF, but i let the engine warm up for 5-7 mins. at the temp gauge is at the third line from the bottom. i think that is the normal temp for the engine?? but somehow i don't switch to my fourth gear.. stays at third for awhile.. so what i should do is wait a lil longer than usual??

 

Wrong, there is a temp sensor in the tranny. You can see it if you take the pan down. The TQ locks up when the transmission fluid gets up to a set temperature. It has nothing to do with water temp. Why would it? That makes no sense at all.

 

I've noticed the tranny won't lock up until well after (sometimes 5 minutes after) the water temp. has reached normal when it is really cold out. This leads me to believe that water temp is not a factor. I didn't know there was a sensor in the tranny, but it doesn't surprise me.

 

On my dads Camry the tranny will not go into 4th gear after I start driving when the car has been standing still. I read somewhere that a car does this becasue the tranny oil is not up to running temperature and it will only shift when it warms up.

 

how about getting redline ATF or mobil?? does that help make the tranny fluid temp rise faster... cuz all i know it does it shifts smoother when its cold... err maybe sometimes..

 

I don't think that it makes it rise faster in temperature but It should lubricate the tranny internals allowing them to handle extreme temp. better, less wear and tear and a little more power to the wheels. Like 1hp or 2hp.