Another thread reminded me of a question I've been meaning to ask. A friend has a 2004 Corolla with an automatic transmission. I helped him replace a drive axle. As expected, transmission fluid leaked out. I made it a point to tell him that we must use the proper fluid, as specified by the manual. After picking up the new axle, we didn't find Toyota ATF Type T-IV at the parts store. We went to the dealer to get a quart. After getting the fluid, the guy at the parts counter told us next time we could use Dexron III from any parts store. On the bottle, it says something substantially similar to "this fluid replaces Dexron III used in Toyota vehicles." What are the thoughts here? Did the dealer give us the wrong stuff? Or is T-IV just overpriced Dexron III? Something else?