ATF is a great cleaner. Every get really dirty hands, rubs some ATF on them, they will get cleaner, though still slick with oil. Those 5 minute flushes that you buy are mainly just kerosene. Every smell some fuel injector cleaners? They also smell the same way. But what will lube the motor better while you are doing the flush? Kerosene or ATF? ATF is designed to keep the passsages of the transmission clean and clear, as well as keep everything inside of it lubed up. 10 miles of driving with 1 quart of atf in an oil with 4 quarts of oil will not produce those effects. That kind of damage would occur with little to no oil in the crankcase, or using the wrong oil. The way I look at it, ATF will be much safer to use than those flushes. But those flushes are meant to be run for 5-10 minutes, then change the oil. If I ran the ATF, i would run for 20 minutes or so.

Dan