about what milage do transmissions go out for chevys or dodges or fords for that matter

depends on how you take care of them, i got rid of a car with 221k on it never have and tranny work,just keep the fluid and filter changed every 30k, my 75 monte i just got has over 300k and the tranny has never had work other than fluid and filter, my buddy just had his tranny rebuilt in his ford ranger 89k miles on it

take care of the motor, trans, cooling system, brakes, rear end oil, and the vehicle will take care of you