Drain Washer
Body mounts are notorious for collecting water, mud, & salt (especially the RHF which also collects battery acid), resulting in severe corrosion even on well-maintained trucks South of the salt belt. So to reduce future problems (I HOPE), I've packed these with anti-seize (Winzer AF-1600, Permatex 80078 ), and added a flat washer to cover the gaps in the top factory washer, and then grooved the lower washer to create drains. I SHOULD have grooved the lower bushing's bottom surface, but I didn't think about it in time.
The original lower washer is too thin to groove, and it's bonded to the rubber.

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