I bought my truck mid March. it has 123k miles on it and before i do the magnet test to see if it was replaced, does the plenum usually go bad before 123k miles?

 

They can go bad when the motor is first started at the factory for all any one knows. I highly doubt yours has been replaced with an aluminum pan. Someone would have had to do that. It doesn't come from the factory with the alum. pan.

 

Just do the magnet test, takes a whole what 5 minutes zman? If that. Open hood, take air cleaner off, lift up side to open ports, stick telescoping pen magnet and test. Why be in doubt?

 

Unless he bought the truck from someone here on DF. I doubt the pan is aluminum.