If you click on the Wheel Well Liner Installation Video above... there is a Direct Link on screen that will take you to their Sales Site...and after doing so and looking around their site... I found a whole range of Bed Liners there On Sale as well... and I so got the durable quality elevated drain-able one offered for $89.00 when I ordered these Wheel Liners. Their site is Way Cool to wander around in for many more accessories ...but when it comes time to actually Place an Order ...you have to select the Correct Product Number from one Screen before it takes you to a screen that you lets you add items to your Cart.
I agree with
@smt 59 regarding the additional corrosion potential... but by smearing some Fiber-Glass Reinforced Roofing Tar around the inside perimeters of the Wheel Well Sheet Metal before popping these liners inside that action might help with the problem and by removing them seasonally for a good Salt and Dirt Wash Down might discourage the thin metal from such regular decay and rust. They look like they would come out from under the truck bed just about as easy as they appear to install. If nothing else... Brown Snow and Salt Slush would have a whole lot less of a chance to build up and stick to these black plastic inserts than on the ordinary Nooks and Crannies present under there as stock spaces and framing as can be seen clearly in this video, very exposed to the elements being slung around by the Large Tires and decorating everything adjacent the Rear Wheels:
I’m guessing this is the result of what
@smt 59 suggested earlier that occurs when the unprotected, dinged up sheet metal areas under the Wheel Wells gets all Beat to Hell from the Big Tires slinging road rocks ...and then the road salt getting to “Make a Meal of the Sheet Metal”. So if the damage has already been done like this ...these videos will show how to “UnPh*** the Truck” with some Elbow Grease... some Inexpensive Replacement Shaped Body Panels, Some Body Filler and Some Paint:
Part I
Part II
...and What the Hell… While we’re at it… We might as well do the Rocker Panels, too:
https://www.youtube.com/watch?v=EbwfYb3h2oU
(No Animals were harmed during the making of this production….) ;>)