Preheat your oven to 250°F (120°C).
In a large mixing bowl, combine the vegetable oil, ranch dressing mix, garlic powder, cayenne pepper, onion powder, and dill weed (if using). Whisk until smooth.
Place the saltine crackers in the bowl and gently fold them into the seasoning mixture until they are well-coated.
Spread the crackers in a single layer on a large baking sheet lined with parchment paper.
Bake in the preheated oven for 30 minutes, stirring halfway through for even coating.
Remove from the oven and let them cool completely on the baking sheet before serving or storing.