Does any have done it before (Transmission Fluid Change)?...I couldn't find anything on the repair manual about this.

thank you

What's your vehicle ? I just replaced the tranny fluid on an 03 Ody. The Haynes manual for that vehicle covers the topic. It's fairly straightfoward - the only thing a bit difficult is locating and removing the fill plug but once that's done, it'll take you about 15 minutes for entire process.