Looking to undercoat my rear wheel wells for the winter (salt) and am wondering if anyone has had success with a certain product. Right now, I am considering 3M Rubberized Undercoating and Duplicolor Bedliner. I'm afraid of the rubberized undercoating "attracting" too many rocks/etc, therefore leading to places where water and salt can weep into. And as for Bedliner (aerosol), I'm wondering what kind of texture it will leave as I'd rather not have that severe "wrinkle finish" look that I tend to see on most truck beds inside the wells.

 

Another option is Fluid Film. I hear good things about this product.

 

I just went to their website. I too was impressed until I saw this:

Care should be taken around non oil resistant rubber goods. May cause swelling. Fluid Film may soften some vehicle undercoatings. This includes undercoating type paints. Check with dealer/manufacturer for compatibility.

 

If you drive thru salt leave undersides alone as long as temperature is below freezing (for months in some locales) Once thawing temp is reached diy car wash undersides. IMHO

 

I like the rubberized products myself, they seal well and remain flexible and can absorb rocks flinging upwards.