OdesiTT

Car: 2006 350Z Grand Touring AT
Hi! 6 month ago I brough my car to Nissan s dealership and they changed my ATF(just change, not flush). Car was running well, but I decided to check the level, because I noticed some kickdown delay. It s appeared that the ATF level was to high (as I thought). I drained quart(yes, I m stupid) and believe me or not, car start to run better. But I noticed that when I m manually shift from 3 to 2, and pressing the gas pedal immediately, car shows that I m in gear, but instead of acceleration, it s just rev the engine and catching the gear after about 1 sec! It s seems like it doesn t slip, because upshifting is flawless and immediate. I know about ATF temperature and level relation and NOW I know that I have to check level when car is idling. I added a quart of Matic S but problem is still here. Please help!

OdesiTT

Maybe fluid went from stall converter?

rancor

So are you saying you ran the transmission low on fluid(quart down), then later refilled it but problem persists? It's not a problem I have heard of before, maybe try resetting the ecu so the transmission can do a relearn?

Any reason you didn't do a flush?

OdesiTT

I changed fluid next day after I bought this Z. There was 89k on the clock so I did it right before the deadline. I know that I can change it and probably I need to do it but I afraid it may start to slip. This is my first AT car and I hate this transmission. 350Z(Literally a sport car) have no SPORT mode while G35(luxury sedan) doe's. This is weird. Moreover, kickdown and shift-points is unpredictable. However, in manual mode it's not worst than stick. Maybe it's this particular transmission, I don't know.
If somebody have AT transmission, share your impressions

rancor

Other than the transmission being on the slow side it actually one of my favorite ATs. For me it's the one transmission that generally does what I want it to and I can predict. But it took a few months to learn to let the transmission do its thing and not to try to trick it into doing what you think it should. Use manual mode when you want that. I have not driven a G35 but the 350Z might be in sport mode all the time and just not have a luxury mode.

Also think of the gas peddle as a requested wheel torque. This might help you change some of your habits from driving a manual that are making you hate this transmission. The transmission is a learning transmission so resetting the ECU and letting it learn your driving habits should help.

You can do a few more pan changes if you want, but you are only changing 3-4 quarts out of 12 or so. You will need to do quite a few of these you actually change a significant portion of the fluid. Four changes of 3.5 quarts would be ~75% new fluid. This is why a "flush" is recommended. I put flush in quotes because nissan just lets the transmission do fluid exchange with its internal pump not with a external power flush that could damage the valve body. I would recommend using the nissan dealer for this a they will use the proper fluid. If the current fluid is very brown or burnt smelling you need to change it.

If it slips after a change it was probably dead before the change and the amount of friction material in the fluid was limping it along.

At this point if I bought the car again I would get a manual, but I wouldn't sell my current Z just for a manual.

OdesiTT

I've adjusted fluid level according to trans. temp. and problem disappear. Thanks to everyone!

rancor

Glad to hear it, enjoy the car .