I took mine to dealership for a checkup (had smoke coming out of exhaust). Just got the car a few weeks ago, 44k miles on it..... They said I needed to change tranny fluid, looked like it had never been changed. I did some research on this forum and auto part store also said to use a 80w-90 and I hear a lot about mt-90. When I asked dealer what they used, he said it was like a 5 or 10w - 30? Told me that's what's recommended, but he is the ONLY person that has said that. I honestly don't trust the b@$t@rd. He also told me that a 90 is way to thick and the car won't drive right. Thinkin about doing it myself when I install my rear MM, although I'd rather not (kinda lazy and don't mind payin money for it). I don't know to much about fluids, what do you guys think about what the dealer is trying to put in my car? What is the difference between the different tranny fluid/gear fluids? OR, is there already a thread explaining this?