I posted this on the WRX site but as a new owner, thought it belonged here. I have a 2001 Outback wagon, 2.5 L, 4-speed automatic. Is it safe and/or preferable to use 3 around town instead of D, particularly in hilly Ithaca, NY? Is shifting in and out of D (overdrive) OK?
yeah it will not hurt the tranny at all to shift it manually. Normally it is not necessary to do so unless the tranny is hunting for gears meaning shifting up and down several times when going up a hill. That is usually not a problem with those tranny's though. Don't worry about shifting it manually though it will not hurt it.