[JRTJH]

As trailers become lighter, many innovations have been incorporated to help reduce overall weight. Some have been very successful, some, not so much. One of the successful products has been DARCO as a replacement for the older "tin wheelwells" on trailers that sometimes weighed two times what today's models weigh. If you think "blue poly reinforced tarp", that's essentially what DARCO is. Although it's stronger than most "blue tarps" it's built much the same way. It's been used in travel trailers as a bottom liner/wheelwell liner for about the past 10 years. Before that, it was used (and still is used) as the undercovering for mobile homes to seal the "basement" where insulation, heat ducting and plumbing runs are located.

Most travel trailers now use DARCO in the wheelwells and either DARCO or COROPLAST (corrugated plastic) as the "bottom seal". Both are waterproof (not water resistant) and as long as the structural integrity is maintained, DARCO is a great choice for wheelwells. The only "downside" is damage from rocks/blown tires. That damage should be repaired ASAP using an approved tape, applied properly.

That said, many owners are probably sitting in their easy chair reading this thread and wondering, "Do I have that in my wheelwells?".... I'd submit that they are already "behind the power curve" because the DARCO lining in your wheelwells really needs to be inspected and maintained, just like the axles, wheels, bearings and tire pressure is maintained. Wheelwells, just like the rest of your trailer need to be inspected for damage, repaired and maintained on a regular basis.

Nobody ever said RV ownership was easy. This is just another part of keeping up with the maintenance.