I also seem to have begun developing rust in several spots at the bottom of doors and windows, with one noticeable bubble under the windshield on driver's side?
Don
Can't help with the weatherstrip, but having owned a VW bus I know a couple things about rust.
#1) You can treat small areas with phosphoric acid (sold as Ospho, also the active ingredient in naval jelly).
#2) Make a saturated solution of washing soda (sodium carbonate). Get a 12v battery charger, attach a piece of scrap metal to the positive electode and submerge it. Attach the part to be cleaned to the negative side and submerge. Don't let them touch. Put the charger on the lowest setting and leave overnight. It works very well. I use a kitty litter pan for largish parts and an old tupperware for smaller ones. Just did my doorhandles since the brackets were leaving rust streaks down my nice paint <img src="/forums/images/graemlins/wink.gif" alt="" />
You can even do door bottoms too - dig a trench, and put a plastic tarp in it and submerge the lower edge of your door (AFTER taking it off the truck, unless it's a really big trench!). I have been planning to do this to my rear barn door (the only rusty spot on my truck, other than some suspension areas - very minor). Standard disclaimers apply, don't electrocute yourself, etc.
One caveat- this will lift paint on aluminum (chemists?). Discovered this on the door handles which are aluminum, hinges are steel though, hence the rust.
