I have been negligent regarding the timeliness of replacing my transmission fluid on my 2007 Honda CRV. Have 70K miles without changing and was told by dealership that it should be drained and refilled because it was no longer pink-ish in color and was brown. I asked about flushing and they said something about the pressure may damage the "celenoids?" and cause the transmission to not shift smoothly. I asked 2 different mechanics at local gas stations and they each said to flush it (although one said that if the fluid was black he wouldn't advise flushing and just replace, and the other said that if over 100K, that flushing could cause the transmission not to shift smoothly).
The dealership wanted 120 to drain and replace, the gas station mechanics want approx 240 to flush.
I would like to perform one or the other and am seeking advice as to which.