Position rack in center of oven and preheat oven to 350°F.
In a large bowl, combine the oats, coconut, pecans, and walnuts. In a measuring cup or small bowl, whisk together the melted coconut oil, pumpkin puree, pumpkin pie spice, and salt. Drizzle the oil/pumpkin mixture over the dry ingredients in the bowl and stir well to combine. Drizzle the maple syrup on top and mix until all ingredients are evenly coated.
Transfer the granola onto a 13"x18"x1" rimmed half sheet pan and spread into an even layer. Bake, stirring and flipping with a wooden spoon every 10 minutes, until the mixture turns a nice, even, golden brown, about 30 minutes total. Watch carefully for the last 10 minutes of baking time, checking every few minutes and stirring as necessary to prevent over-browning.
Remove the granola from the oven and stir frequently as it cools, scraping the bottom of the pan to prevent sticking. Once completely cool, store in an airtight container.