The AOD is a very easy transmission to service with fluid and filter kit, shouldn't cost any more then $30--40.00 at most for fluid and filter kit so at that price it would hurt to change it, an hour from start to clean up IMO, make sure all the bolt holes on the pan lip are flat not dimpled causing any leaks from over torquing.
I like to use RTV Ultra Copper sealer for the pan gasket because it sets up quickly and won't move around on you when you put it back, again so there are no leaks leak.
You can get the two bolts straight out at the back of the pan using a 13/32" socket, small ratchet, hand turn etc. http://www.supermotors.net/registry/media/676395
Use two tie wraps on the last two pan side bolt holes towards the back to control drainage and minimze the mess, easy peasy. I have a 25 gallon storage tub that fits underneath nicley.
There's also a simple adjustment (Haynes Manual) you can perfom underneath on the drivers side to insure the column shift linkage is in sync with the transmission, over time bushings can get sloppy, key on engine off pulling the column shifter down into the fisrt (D) position secure it so it can move, going underneath losen the column shift linkage "BOLT" just enough to click the transmission "TAB" all the way back until it stops, 2 clicks forward then tighten the "BOLT" place back in P turn off the key and now the PRNDDL in is sync.
Make sure all the u-joints fittings are torqued and greased it will make take off and shifting smoother if there are any issues being loose.
Use this video as reference to adjust the TV cable up above it's very important it's done right or you'll burn up the transmission in no time...http://www.youtube.com/watch?v=6L3hNzxdiYw
DO NOT USE use any type of transmission "flush" as you may disturb the particulate built up in the fluid inside keeping the transmission working if you have high mileage on it, just keep it topped off.
Good Luck ~