It appears that from the original install the drain hoses were not properly routed through a hole/grommet to the ground. As it is now, the left drain hose deposits water directly under the cargo cover. And the right drain hose is missing entirely, which deposits some water under the cargo cover and some on top. Total fail. I was able to order a new set of hoses. And I did a little measuring and drilling with a step bit. I douched the holes from the top and bottom with surface shield (rather than bother with paint).
The hoses are kind of interference fit and I pulled them down to one "click" of the corrugated hose so they should stay put. This is great and I wish this was done originally.
I actually did the drilling before I received my missing hose. Fortunately the new hose was the same as the old hose. I just reused the left hose which was already there and used one of the new ones for the pass side.
2010 Tundra: fix tonneau cover drains
2010 Tundra: fix tonneau cover drains
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