I think the main reason people are steered away from changing it is the potential to disturb debris or particles or pressures etc that can affect operation, the dealers seem quite adamant it's lifetime, personally I've always been of the opinion it's far better changed, a caveat being changed 'more often' perhaps, or the owner take the risks of loss of function or change in characteristics at least, that they might not like. One cannot see inside and one cannot undo/reverse the job once requested ;O)
Transmission ECU's adapt as do engine, and they communicate, so there is potential for some degree of affect imo. I personally wouldn't be deterred but on a car of my own perhaps more than a customers, especially one looking to have it done for the first time at this mileage, it's likely to exhibit a greater difference in shift characteristics than one having had it changed twice before for example. Only my own view, no reason not to do it, just food for thought perhaps. I have seen instances where a symptomatic transmission has had a fluid change and deteriorated after, this is not the same as routine on a fault code free fully functional system, just saying that stuff happens.
Fwiw in the last scenario I'd change the filter in the final change. Some car models might need to run the motor while pumping fluid through to flush a torque converter, haven't had to do it personally, some Mercedes for example, whether anyone's done it on something like this who knows. I'd opt to change it a couple of times, and did actually on my 172k CL500 when I got it, wasn't that bad in colour really but wasn't clean and the pan had a sediment film on it hence done again a few months later just because....
If it misbehaves after changing I would look at an adaption reset, then use it for a while to see how it settles.
Transmission ECU's adapt as do engine, and they communicate, so there is potential for some degree of affect imo. I personally wouldn't be deterred but on a car of my own perhaps more than a customers, especially one looking to have it done for the first time at this mileage, it's likely to exhibit a greater difference in shift characteristics than one having had it changed twice before for example. Only my own view, no reason not to do it, just food for thought perhaps. I have seen instances where a symptomatic transmission has had a fluid change and deteriorated after, this is not the same as routine on a fault code free fully functional system, just saying that stuff happens.
Fwiw in the last scenario I'd change the filter in the final change. Some car models might need to run the motor while pumping fluid through to flush a torque converter, haven't had to do it personally, some Mercedes for example, whether anyone's done it on something like this who knows. I'd opt to change it a couple of times, and did actually on my 172k CL500 when I got it, wasn't that bad in colour really but wasn't clean and the pan had a sediment film on it hence done again a few months later just because....
If it misbehaves after changing I would look at an adaption reset, then use it for a while to see how it settles.
