My 2000 has 30,000 Mi. on it and I had it flushed once about 6 years ago, at around 12,000 Mi. I believe. As Tyler said, yours is certainly not neglected but wouldn't hurt to do it (mine too). Flushing alone is good but only on low mileage cars. As the miles roll up, (over 50,000) and especially if you run your car hard a lot, the pan needs to be dropped and the filter changed also. If you do the work yourself you can pull the pan, change the filter(and seal), and replace the fluid. At this time inspect the bottom of the tranny pan. A light grey particle residue no larger than a teaspoon worth is ok, that's normal wear. If it's a large amount, black, and large pieces are found, you're looking at a rebuild down the road. Hopefully yours looks ok. At that point you can button it up and you're done. Trouble is , you've only changed about a third to one half of the fluid. Because they don't put drain plugs on the torque converters anymore you can't get any more fluid out. Most folks stop here and call it "good enough''. You can however', unhook the trans cooler lines, feed clean atf to one line and flush it out yourself with the engine running at idle until fluid comes out clean at the other line. Just make sure your supply of atf doesn't run dry. On low mileage cars age of the fluid is just as an important factor as mileage because over time with the heating and cooling cycles, winter storage, short trips, etc... the fluid will pick up moisture in the form of condensation. Also the conventional atf will lose it's protective properties over time, so it's just wise to change it out, cheap insurance to hopefully make that tranny last the life of the car. One more thing, when you do change it switch to synthetic, something like Castrol Dextron VI. It is compatable with the conventional Dextron III, just in case there's any left in there,(the Mobil-1 is not it will make sludge if mixed). With the synthetic you will get better protection, less friction, less heat, longer service intervals, and will even pick up a couple of ponies!!

Dave