Deja Vu (and my opinion) regarding "lifetime ATF"...
Thanks for all the good info in this thread. So is this Ford document about the very same problem that was solved years ago with the 06J valve body in our caRs?
My caR was built at the end of Jan '07 and its AW 6-spd is an 06L. No issues, approaching 33K mi. Shifts are always somewhat harder (faster; more abrupt) when in Advanced (actually, whenever it's in "S" mode, which Advanced triggers independent of the "S" switch) -- I sometimes notice upshifts into 5th and 6th when in "S" mode (in fact, given the location of the "S" mode indicator, that's often my best/only indication)! (my tranny feels more solid than any automatic I've ever known) ...the next time I see my friend's March '07 VR (the last run of VRs, I believe), I'll try to remember to check to see if it's beyond an 06L
I'm getting a sense of deja vu regarding "lifetime fluid", from more than 10 years ago. V started that back with the 850, which used a 4-spd AW. One FFE (factory field engineer) told me that there'd been internal talk of either leaving out the dipstick entirely, or even including a ('fake') dipstick to some dummy reservoir! Clearly, this topic gives rise to lots of differing viewpoints...
Back then, some over-maintenance-freak V owners thought it'd be a good idea to drain and refill their 850 Turbo's ATF with each oil change. However, most of those over-maintenance types sold theirs and bought BMWs long before it made any difference at all what they did to their AWs...
My 854T was the ultimate driveable appliance. It thrived on neglect. Its AW was still going strong -- having never missed a shift or even a beat -- at 222K mi. Back in its youth, I drove it pretty hard, including once spinning the wheels virtually the entire way up the top half of the Pikes Peak Hill Climb race course. Amidst all the chicken-little ATF internet talk by the over-maintainers, I decided that maybe I should not wait until the 70K mi timing belt interval to freshen the ATF, and had it flushed (just disconnect the line to the radiator and let the AT pump suck in clean and push out old) at 64K miles (with many hard PP runs behind it, the fluid was no longer so red and fresh-smelling). It made no significant difference to the operation of the AW AT.
I did the 2nd timing belt change at 145K mi, and the ATF was 'preventively' flushed then, too. Again, no difference.
FWIW, I had essentially the same AW in my previous car, a Mazda. That one came from the factory misaligned between the flywheel and the torque converter, resulting in a vibration at 56(?) mph. By the time this error was relieved, permanent damage had been done. The warranty repl tranny came with a leak, so was repl. The 2nd warranty repl tranny came with a bad PRNDL switch! Anyway, that car was worn out at a little past 120K miles, so I only put maybe 70K mi on that (last) AW. Still, a very good unit; among the 3 in that car, only 1 beat/shift was ever missed, and that was on Pikes Peak when I abruptly changed my mind with the throttle just as the AW was making its shift decision (that was in an '80s car; by the '90s, the 850's AW's ECU apparently was fast enough that that never could happen). I was then, from my old AT days (more on that in a paragraph or 2...), still pretty fastidious about changing ATF, and several times pulled the pan. The first time, the 2 oil pan magnets were fully/shockingly covered in metal shavings (which were removed/cleaned during servicing). Subsequent drains/fills looked nothing like that...
So that's my experience. Here's my opinion/view on modern ATF life:
Back in the olden (1960s/1970s) days, pre-lockup-torque-converters, the (molecules in the) ATF was being constantly sheared (chewed up) by the AT (IOW, by the old-fashioned always-slipping heat-generating energy-wasting torque converter) whenever it was in gear. Back then, if you wanted your AT to last 'forever', all you needed to do was to change the fluid every 2 years or 25K miles.
Since then, lock-up TCs mean that the ATF molecules are not constantly being sheared; in fact, they hardly ever are. Also, ATF has improved drastically since the 1970s. So it's not totally out of the question for ATF to survive for 250K miles! IMHO, that's what the V engineers were smoking when they came up with "lifetime fluid".
Keep in mind that the biggest enemies of ATF are oxidation and contamination(/dirt). Doing additional/excessive ATF changes is the best way of introducing the #1 enemies of ATF into the system.
My car's still a pup, and I haven't worried about fluids yet, so I'm still quite ignorant about them. I know that some of the drivetrain fluids are pretty specialized. I don't know if my factory ATF fill is synthetic or not... I do know that I'm not a big believer in switching to synthetic ATF, given that Dexron (what my 4-spd AWs used) was already the most highly over-engineered fluid in the car, and also that synthetic engine oil's 2 biggest advantages -- friction reduction and tolerance of combustion-like temps -- are not as desirable/necessary in an AT as in an engine.
As long as the ATF doesn't over-heat, it shouldn't over-oxidize, and should, if left alone, remain good and functional for a darn long time. If the fluid becomes/is bad, that's virtually always a SYMPTOM of a problem, NOT a cause!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! (...just as leukemia cannot be cured by performing a complete blood transfusion...) Changing the fluid will then serve to mask the problem, which can be a doubly-bad idea if the vehicle's still under warranty...
It's easy to laugh at "forever", but even easier to try to out-think V and over-maintain without benefit (or even with detriment!). I continue to reckon/believe/advise that the timing belt definitely needs changing more frequently than does the ATF. (And therefore that replacing the ATF along with the timing belt should be [more than] sufficient over-maintenance. Now, let the optimal timing belt replacement interval argument commence...)
