Engine light blinking 6k miles after transmission replacement. At 57000 miles, finally had faulty transmission acknowledged by dealer. The car had a loud, rounded humming sound on occasion that was grating to the ear. Also, as mentioned in this thread, at very low speeds with windows down a light metal on metal abrasion sound. The dealer needed to be pushed to determine a new transmission was needed. They said they have to run several tests and their diagnostics computers have to spit out the right codes which mean that the transmission 'failed by enough' in order to get authorization to order new transmission. I was empowered to persist by an independent mechanic saying to me, "We could help you but the problem is definitely the transmission and you are under warranty so take it to Ford." And the advice of this forum. Took a 5000 mile summer trip with very little extraneous noise and improved gas mileage by a gallon or two. Then the engine light came on blinking last week. Car shuddered and trembled with even minor acceleration. Manual says using the car with blinking engine light indicates misfire and can damage catalytic converter. Garaged car for a couple days. No light on and no tremors. Taken immediately to Ford. They have a TSB for this, too. Reboot/update software. Costs $240. Ridiculous. Car seems good now. For one day.