I went to my local AutoZone on Sunday with a little over 5 gallons of used motor oil and ATF; they were in the translucent Amsoil 1 gallon jugs. The manager asked me if I was bringing oil for disposal and I said "yes" and he said "OK". When he saw the red fluid, he asked me if it was ATF, I said "yes". He then told me he wasn't going to take any of the stuff so I left the store. I don't know why he was willing to take the used motor oil but balked at the ATF. Isn't ATF basically a light weight oil with some additives and red dye? What is in ATF that can't be mixed with used oil or does the store manager not know that they can be mixed and refined. I realize antifreeze must be disposed of separately, I would suspect conventional brake fluid could be mixed with antifreeze, but couldn't gear oil and ATF be safely mixed with motor oil without contaminating the whole drum? TIA for any information.