Section 149 (Ignition System (Service Information)): Specifications: 3.6L
WARNING: This page is about a different car, the 2016 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Firing Order: 1 - 2 - 3 - 4 - 5 - 6
Courtesy of CHRYSLER GROUP, LLC
The firing order for the 3.6L engine is 1 - 2 - 3 - 4 - 5 - 6.