Sealed for life in the hands of the first owner maybe and to Hades with the subsequent owners they are not the target of the new car sales campaign.
IMO every 50K is probably a good bet with synthetic fluid and change/clean the filter/screen and pan if its serviceable.
You don't mean service something that the engineers and designers deemed never needs service do you? That would mean you know more than they do.
j/k
All kidding aside, filled for life is one of the dumbest terms to come out of the auto industry in a long time. [/
Funny thing - I recently met a guy who is part owner of a transmission shop. We got on this subject of changing tranny fluid. He said he didn't think actually changing the fluid made any difference at all in the longevity of most transmissions. His theory is that in most (he estimated at least 8 of 10) vehicles that he sees, the fluid was extremely low. He said most people don't check the fluid level ever (if it is possible) or notice the puddle of fluid under the car and drive the car until the tranny starts to slip, then they either drive it to a shop or drive it until it completely dies. Either way most of the time the tranny is toast.
He said he sees a lot of leaking seals in certain models. Also he smiled when he mentioned he has seen a number of tranny pans that were severely damaged (mostly FWD vehicles) and the owner came in bad mouthing the manufacturer for making a POS vehicle.
Personally in my 50+ years I've owned a lot of vehicles and serviced many many more. I've seen vehicles that from the factory needed a transmission rebuilt while under factory warranty, and I've seen vehicles that were bought new and were sold or send to the junkyard 200K - 250K miles later that had the factory tranny fluid and still shifted fine.
I realize everyone has their own stories and experiences. I have gone both ways in my own vehicles but can't remember the last time I've had a tranny failure.
But - just maybe those engineers and designers aren't as stupid as you think they are!
+1
