I bought an 07 G35 sedan about a month ago with 135K miles. I asked the PO if he had changed the transmission fluid or if he knew it had been changed at any point before he got it and he said he didn't change it. I've been reading through the forums and there are many opinions. Some say should be changed only every 100K miles, some say with every 3 oil changes. Some say with higher mileage cars its better not to change it at all or to just drain and fill, while others say flushing is the best option, even though that goes against what Infiniti itself apparently says in some documents somewhere.

Should I get it changed? There aren't any Infiniti dealerships around so I was thinking I could take it to a NIssan dealership. Even then according to the forums, some dealerships never flush while others always flush it. Its all quite confusing.

 

Fluid change interval is every 30k miles, "don't change the oil" is a complete myth just like "you can't go back to conventional oil if you ever use synthetic".

Never power flush a transmission, there is a drain plug, drain out the old fluid and add new, only use Nissan Matic J or Matic S. It takes about 4 quarts. The filter is a permanent screen style and does not require servicing.

 

+1... don't flush. I paid a dealer to do a flush back in 2014 and about 4 months later the TC went out. Fortunately under extended Infiniti Elite warranty.

 

Will u actually get 4 quarts of oil to drain just by removing the plug?

 

Nissan recommends changing AT fluid every 30K miles, living in a warmer state that isn't nearly often enough! I haven't gone to a Infiniti stealership since '04 when they told me AT service was $280! Nissan charges less than half of that, my opinion their mechanics are better trained too! Flushing isn't an option, even Nissan doesn't recommend doing so! Just have Nissan do a "Drain & Fill," if the fluid is extremely degraded have it done again in 6 months! Our AT work on line pressure, they must be kept clean and free of any type of burnt fluid or build up!
Gary

 

Having not looked at my car, autozone sells a filter. Everyone is saying just drain and refill, do not replace the filter?

 

Correct, do not replace the filter. It's behind the valve body/TCM and is a permanent style filter.

 

Very true. Dont replace filter unless trans fluid pressure is low. I found a cool video on yuoutube of a guy moving valve body temporarily away while he replaced the filter in his drive way. Its definatly possible and not hard!
Oh btw, Matic S has superseeded Matic J. Dont even bother asking for the Matic J.

 

Just got it done today at a Nissan dealership. They did a drain and fill. @gary c mentioned that their Nissan dealership charges less than half of $280 but the one here charged a little over $200. But the transmission feels slightly smoother now. I think. May just be the placebo effect.

 

Anyone know the answer to this?

 

This answer is only from reading a lot of posts here (my current addiction): but that sounds about right. IIRC, tranny holds about 12 qt. This is why you see the recommendation to do about three drain and fills with a little bit of driving in between. You'll gently get the fluid refresh without the trauma of a flush. There is enough anecdotal information to give some credence to suggest that a tranny with neglected fluids does not respond well to a power flush process.

 

Cool. Thanks man!

 

You betcha. Just measure what comes out and put the same amount in.