If you disconnect a speedometer on a 4.2 f 150 is there a way that the dealership can find out how many kms are actually on the truck?

 

what year?

 

I would have to say........YES they can, all they have to do is connect there scanner to the PCM and they can tell you just about anything that was connected or disconnected including the speed o meter.............

Question is..........why do you want to disconnect it anyway

 

Odometer fraud, most likely.