This talk of rust on Reject's post got me thinking. I've thought about this before and curious what other might think.

I was thinking about cleaning the inner fender area really good, scuffing it and spraying some bedliner like the Duplicolor Bed Armor or some other bedliner stuff.

This is mostly for the back as the front is mostly plastic anyways and not quite as prone to rust as the front is but i might do that up front on the metal inner fender parts leaving the plastic as is.

My thoughts is that the bedliner would do a few things:

1. keep water away from the metal
2. protect from road debris
3. make road debris not sound as loud (i hope)
4. possibly make snow not stick as much in winter (also i hope)

So, what do you guys think? does this sound like something that would make a difference? Keep my currently rust free truck (other then my rear bumper but that is my fault) rust free in the wheel openings. I might experiment with this over the summer anyways. I think i have a few spray cans of Duplicolor Bed Armor kicking around. I have to respray my bed anyways. Darn stuff is not as strong as it says it is and keeps scraping off. I don't want to pay the local Line-x shop to remove what i put on to spray their stuff.

 

Spray on bedliner might be a bit more heavy duty than your typical rubberized undercoating, so I would think that it wouldn't really hurt. You'll probably want to remove any factory undercoating to get good adhesion. Generally the wheel well areas have a couple of weep holes for water and condensation to drain from to try and prevent rust issues, (of course it doesn't help Dodge trucks too well for some reason.) I would suggest you try to keep them from getting covered if possible.

I've been told by a body shop that a quick spray of WD40 from a can with a wide pattern will help displace the water out of the seams where it collects. Might be worth doing once every couple of months, especially after you've put some elbow grease into your wheel wells.

 

Ive had no luck with spray-on (DIY) bed liners, Bed Armour sprayed on super thick and runny. Both Ive used are not chemical resistant, especially to gas or stuck very well, either chips or flaked off. I used the Roll-On Bed Armour for the Cargo trailers wood floor, but spilled some gas and had a huge mess.
To keep the water out we have a Oil-based undercoat here that works great, but it was never applied to the truck, plan to do it when i replace the box, but needs to be done every year or two.

I coated both my front fenders, and frame in Spray-on undercoat when I replaced the radiator support, The fenders had no rust at all

 

the problem with any spray on material is any moisture at all or corrosion already present (that may not be visible yet) gets trapped under the stuff, I have repaired cars that had ziebart done and the only thing holding the fender together was that undercoating. I would use a rust neutralizer (rust mort or similar) then por 15 then top with undercoating and paint

 

It'll work for a while but you are unlikely to keep the rust in the fenders at bay indefintely as the problem is found on the back of the weld between inner and outer fenders where dodge sprayed that stupid ****ing foam that holds moisture and dirt causing it to rot from the inside out.

I ground out as much fender rust as I could, por15'd and roll on bedlined it and now about 2 years later the rust is coming back.