I took my car in the shop and they tell me the my 2nd and 3rd plate or something like that are bad and they will fix it, but they said it would be a minimum of $1300. I know nothing about trannys so is this reasonable? Should I get a used tranny and replace it? I looked to MMS and they have trannys for $400. The car is a 2003 GP 3.1 motor.