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The "general", stress "general", recommendations are:
Change oil when the Oil Life Monitor says to, OR once per year regardless of mileage;
Clutch fluid as needed to keep it clean looking in the master cylinder, usually a couple times a year, some do it as often as every month or more often, depending on driving, use and appearance. Follow the "Ranger Method" to do it with a turkey baster from the master cylinder;
If you are noticing any shift issues, gear nibble, or grinding I would change out the trans fluid too. The fluid degrades with time; yours has over 5 years on it. For the money it is a cheap preventive measure.
I changed my '07 OE differential oil at 10k. Used the latest GM recommended fluid # 88862624 Dexron LS. It made a huge difference! Pricey ($35.00 a quart), but worth it.