So from what I can tell there have been multiple years now that the G37 has had the sealed transmission for autos not requiring service. I know many here have done a drain or flush anyways.
I am starting to see lots of other makes also have the sealed system.

So just wondering what is the greatest mileage anyone has on their automatic transmissions without failure and without performing any service whatsover on them, except the software updates.

 

Great question

 

Changed the fluid on my G35 at 110k miles. Sold it with 130k and no problem. Like anything else, life is affected by use. My car was used for highway mileage to/from work. If someone was racing or towing, lifetime would be shorter.

Much behavior is driven by the dealership selling services that are not needed. In order to determine if fluid was truly in need of replacement, it would need to be sent to a lab for analysis.

That being said, I plan on changing the fluid in my transmission etc at 75k miles because I plan on keeping it for a long time--- perhaps 150k miles. Better safe than sorry.

Brian