Yes, mine has block rust in the area of the freeze plugs. I had the bumper cover off about a month ago and the metal support that the cover support bolts to was very rusty. Enough that I need to scrap it down then sand it and use rust encapsulation paint. Also the back chrome inter bumper is rusting. I know that’s a parts no one ever sees but soon or later, the truck would be bleeding rust on the driveway. I doing all I can to keep up with it but the oil pan rust is so bad there is no stopping it. They want seven hundred to replace the pan. I would do it if I could get a carbon fiber pan but no such thing. Hopefully I will dump it before it leaks.

 

Why not use some Por-15 or something like it. that will completely cover it and it's not supposed to get through. I contacted my dealer since I am still under warranty to see what they think. I'm a little disappointed in this, but it is something I am willing to take care of before it gets really bad. Good Luck with your issues Graythang. Maybe it's just us folks in Florida. I know my wifes 06 Jetta has no rust anywhere underneath it. Although it came from the factor with undercoating.