Other than the cab corners, bottom of doors and bottom of tailgate, is there any other areas that are prone to rust? Looking at a truck but its 2 hours away, dealer states he doesn't see any rust bubbles or signs of rust on these areas. Any other area I should have them look before I make the ride

 

Go check it out, man. 2 hours is nothing. Where I live, vehicles are 20-30% more expensive vs. neighbouring states so I only buy from there which is a 2 day trip!

 

My cab corners for sure show some rust but the worst rust area by far is the rocker panels. I have full perforation on the passenger side. If first showed as minor bubbles. Give this whole area a good look. I assume this damage is caused by a leaking third tail light just like the cab corners.

 

What everyone else said is the most important but also look over the back wheels. There is some foam inside the wheel wells between where layers of metal come together. It holds moisture and rusts sooner than some other areas.
Also the hat channels between the box and frame rust out sometimes too.

 

The only spots I have is the rear bumper (constantly hit by snow/dirt/ice) and the inside of my driver door is starting. I used a lot of fluid film on the door when I found that this year.

 

Exact same with my truck (as Spiky saw on my post yesterday), and my rear bumper corners are starting to rust from the inside, not quite visible on the outside but it's only a matter of time.

Check the headliner towards the back for stains. Some 3rd brake lights leak and then water gets down into the cab corners making them rust from the inside out

 

My door is surprising. I've always protected the pinch, and that is fine, no rust even though there's some damaged paint. But, I found bubbling higher up. So, I took off the panel and sprayed everything I can't reach from outside.

 

How easy is it to pull the door card? i'm not sure mine will be as bad, but i also have something rattling in the drivers door if i go over a big enough bump, so maybe a good idea to kill two birds, so to speak.

 

takes less than a minute. lots of videos online on removing them. a couple screws, lift up and pull.

 

So there are, thanks.

This one is pretty straight forward, but assumes two of the panel removals (shows them already started)