Hope I didn't ruin my transmission
 

Had my '07 (45k miles) for a couple of months now. About 6 weeks ago I decide to drain/fill transmission fluid. After reading here, I drain out 4.5 quarts and put the same amount back in. I checked the dipstick but it had fluid all up the side so I just left it. I also had the ECU throttle update done about the same time.

My daughter drives the car so I didn't notice until last week that the car shifts really harshly. Decide to drain/fill again. Car cold this time so it only drained 3 quarts. I refilled and after reading some hints here, checked the dipstick and there was no fluid on it. Had to add another quart to get it up to the top notch (engine warm, running when checked).

I probably put 400 miles on the car like this, hope I did not permanent damage. Shifting is a lot smoother now.

Most auto trans you check while WARM and RUNNING. Did you do this?

Our ATs use line pressure to make the shifts, only time will tell if you did damage or not!
Let's hope that's how he checked fluid level, that's the only way to get an accurate reading!
Gary

Yes, that's how I checked it (engine running, warmed up, driven about 5 miles). Kept getting the trans oil smeared up the dipstick but then figured it out on how to get dipstick out and minimizing it from picking up the fluid on side of the tube. Then I realized it was low.

You can check it could cold on the autos. It has a cold gauge and running gauge.