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Hey guys, I have a new question. In my auto trans, I've got 2, D3 and D4. Everyone and the Internet all have the same general idea about the gears, but none of it is a complete match. I understand that 2 locks into second gear and that D3 uses less gears and also shifts differently than D4, but I don't completely know what it's for. The general consensus seems to be that two is for climbing hills, towing, driving in slippery conditions, etc. Also that D4 is more fuel economic than D3. My main question is what exactly is D3 for? Also, is D3 better than D4 in a street racing application?