Quote Originally Posted by ka1qyx View Post
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GM has a service bulletin on it, saying trans fl & coolant mixing so that causes this issue.....
What year is your Aveo? The GM TSBs for coolant mixing with tranny fluid are generic and cover a number of different vehicles. But up to now, the only cases I've seen reported of this problem happening to Aveos were with the 2009. Not surprising, but that's the model year they changed the radiator/cooler for Aveos equiped with A/T. Probably a bad batch of that new part got out before they identified the problem with it. Not saying coolant can't mix in Aveos other than '09, just haven't seen any reports of that yet.