I have my Maxima 2009 S for 3 months now. I got it at 82k miles on the odometer. The 1-owner Car had been serviced at a Nissan dealer almost exclusively for its life. I contacted the same dealer and they stated they never touched the CVT fluid before. I went ahead and had my Nissan dealer (different one) drained and refilled with about 4.5 quarts and had them change the external filter along with the fluid (I saw the fluid that came out, it was indeed black but clear with no debris or particles). Nice results and definitely car is smoother, though it shifted very smoothly even before the fluid change, I preferred to do it for the piece of mind.

About a week later, I discovered the app CVTz50 (which is a wonderful little app), bought the full version for $4.99. Hooked it with my BAFX Bluetooth OBDII adapter. It showed the CVT fluid deterioration date is 853

Is it possible for the past 8 years that CVTF deterioration only went up to 853? you think some one did a reset for that value before? I would believe that only Nissan with CONSULT can reset that counter (at least before 2015 to 2016 when talented people came up with adapter and application that can communicate with ECUs and TCMs) and when the Nissan dealer denied they serviced the CVT before it made me curious.

Thanks

 

What does 853 mean, days, miles, hours, left before change, or what? CVT oil change interval for 7th gen is 60K miles driven according to owners manual.

 

Owner's manual states to "inspect" CVT fluid at 60k. Not replace at 60k. Though I don't agree with that and I would do it at 60k if I was my car at that mileage.
CVT fluid deterioration is calculated in ECU. It is recommended to replace fluid if more than 210,000 (per FSM). It's rumored to trip up when fluid gets hotter than 90c (stressed).

 

I too am curious what the 853 represents. An arbitrary value or number of mins before failure or parts per million of contamination?

 

Your Nissan dealer seemed to have done the reset.

 

​​​​​​Could be. But accumulating 853 in just a week? Doubt it
I had another Maxima 2011 the same dealer changed the CVT fluid but did not reset the counter.