Probably cage nuts. You can replace them but you'll need to gain access to the back side of the pillar if you don't already have access. I'm not familiar with the construction of that part of the truck so I don't know how difficult it is to access the back.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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