Question for the bodywork/auto restore guys - Undercoatings!

[onlytrueromeo]

Stripping my MX3, and I've always found it difficult to clean the wheel wells because of the rubber undercoating applied. I decided to wire wheel everything off (taking an excruciatingly long time) so I can re-prime it and either paint or rubberize "undercoat" it with either 3m or a bedliner.

I know of the sound deadening benefits to undercoating - are there any cons besides possibly trapping water? Can I paint over the top of it? Is there a specific brand I should stick to? I know that they also prevent dings/chips to the paint that could rust.

Or should I just skip it, and just WD40 my wheel wells and undercarriage in the winter?

This won't be happening for awhile, but I want to know now since it will determine how much prep work I do on the wheel wells - i.e. if I'm going to paint them, I want them to look fantastic, but if I'm slopping a thick rubber coating on, it won't be smooth and shiny anyway so I won't care about making the surface 100% smooth.

[mitmaks]

I used 3M undercoating. It holds up well, dries fast, good product overall. If you have extra money get it coated with bedliner. Make sure you get in all the corners very well. Most rusty quarter panels I've looked at didn't have undercoating right around inside lip, that's where it started rusting from.

[onlytrueromeo]

I have also seen most rust start from the nooks and crannies of an english muffin, erm, wheel well. That's where I will focus my time as far as prepping/sealing. Can 3m or bedliner *herculiner or equivalent* be painted over? I thought it would be nice to have shiny wheel wells

How easy is the 3m to clean? I know bedliner dries with a rough surface.

[mitmaks]

shiny wheel wells? I dont know about that one...
Should be able to put pressure washer in there and rinse all the crud out in the spring time