Luffy's current peak power is Gear 5, his awakened devil fruit form enhancing his abilities significantly. Gear 6 is unlikely to exist, as Luffy has stated Gear 5 is his pinnacle devil fruit form.

Even in terms of his Devil Fruit progress, there is a lot that Luffy can still work on and learn moving forward, and it is ...

By awakening the powers of his Devil Fruit, Luffy is now able to harness the powers of the sun god, Nika, and become the Warrior of Liberation. While in his Gear 5 state, Luffy is able to take on ...