How do u change the transmission fluid in a 2006 Suzuki aerio awd

Check your transmission fluid level first. With the engine running and in park. Then get back to us.

Ditto what Mark said. If you've never changed transmission fluid before I wouldn't try it. I would recommend a transmission flush instead. When you drop the trans pan to change the fluid it doesn't get all of the fluid from the torque converter, trans. cooler and trans. cooler lines. So if you service the trans, by dropping the pan, when you're done and add the new fluid into it the first time you start up your Suzuki it will mix the new fluid with the old that is left over. With a transmission flush ALL of the old fluid is removed.

It looks like it was a quart low

This transmission does not have a pan on the bottom of the transmission

Ok if it was a quart low that should be your problem. How clean was it? It should look like cherry kool-aid. If its brownish gray and smells burnt, get it flushed, before you burn up the transmission.

Ok no transmission pan. Even more of a reason to bet it flushed.