Quote Originally Posted by Aveo5_boy View Post
I have a 2008 Aveo as well and it is everything as Jayman has explained but you might want to go through pages 5-19 to 5-21 of your owners manual and read up on how to properly check the fluid level and how to properly add the automatic transmission fluid. I did this process 3 times with 1 day intervals to try and remove as much of the old fluid as possible but this method you will find a few will not agree with as it will not remove all of the old fluid.
All true, and here are a few more tips: On any car with an A/T you will never go wrong by draining your A/T fluid every 6 mos. (or at least yearly) when you change your oil. It doesn't need to be done in daily increments, but can be done with each oil change depending on how the fluid looked the last time you drained and refilled it. Degraded fluid hastens transmission failure, and it's one of the most expensive repairs for any car. Been there, done that.

True, you will only replenish about 1/3 of the A/T fluid capacity in doing a drain and refill yourself. But after a few times of doing it you should notice some improvement in color of the fluid. My fluid was brown after the first 10,000 miles and it's still not entirely red after 18,000 miles and several changes later. This has me concerned, but remember: it's better to change degraded fluid than not to change it and have it worsen.

Transmission fluid is relatively cheap compared to the cost of rebuilding a transmission.