I can't say which is better, and haven't used Mobil 1 ATF anyway, but I can comment on using Dexron VI in my non-GM transmission:
The vehicle is a 1997 Infiniti i30, with a Jatco RE4F04A transmission. The manual specifies Nissan matic-D or Dexron III.
I decided on the bargain Dexron VI, which is Supertech. I did a drain and cooler line exchange to replace the Dexron III(H) that had been in there for about 10k miles.
Here is my summary after using the Dexron VI since last August, for about 8,000 miles.
The good: Shifts are slightly better while the transmission is warming up. 1-2 loses the harshness sooner, all shifts are quick as usual, except near WOT where there have always been a little slow for my liking (no change).
Not so good: After it has warmed up thoroughly, the transmission whines where it didn't whine before. Before there was a slight whine at 35-38mph (which is still there), but now there is also a slight whine at 45-50mph and another at 65-70mph.
Why? Perhaps due to the lower viscosity of Dexron VI. I am considering a drain & fill with a higher viscosity ATF in an attempt to banish the new sounds.
The vehicle is a 1997 Infiniti i30, with a Jatco RE4F04A transmission. The manual specifies Nissan matic-D or Dexron III.
I decided on the bargain Dexron VI, which is Supertech. I did a drain and cooler line exchange to replace the Dexron III(H) that had been in there for about 10k miles.
Here is my summary after using the Dexron VI since last August, for about 8,000 miles.
The good: Shifts are slightly better while the transmission is warming up. 1-2 loses the harshness sooner, all shifts are quick as usual, except near WOT where there have always been a little slow for my liking (no change).
Not so good: After it has warmed up thoroughly, the transmission whines where it didn't whine before. Before there was a slight whine at 35-38mph (which is still there), but now there is also a slight whine at 45-50mph and another at 65-70mph.
Why? Perhaps due to the lower viscosity of Dexron VI. I am considering a drain & fill with a higher viscosity ATF in an attempt to banish the new sounds.