I would leave it in "D" unless you expect to stop there for, say, over 5 minutes (if you expect to stop that long, you might as well turn the car off). The low gears (except the 4th) are fluid coupling so I believe there will be minimal wear to the tranny if you leave it in gear while sitting at the light.
What is more important is to make sure you have the ATF changed once in a while - every 15K to 20K is not too often IMO since this is the best insurance! Beyond this, just drive smoothly, avoid sudden acceleration and high speed "down shift" if you want to prolong the tranny life!
What is more important is to make sure you have the ATF changed once in a while - every 15K to 20K is not too often IMO since this is the best insurance! Beyond this, just drive smoothly, avoid sudden acceleration and high speed "down shift" if you want to prolong the tranny life!
