0-40W Mobil 1 is still the main choice. Dodge recently got a new contract with Pennzoil, and a different weight, but virtually all your supporting Vendor Dealers will only use the Mobil 1. We are using 0-40W in all Generations now, and skip the filters out there except for the Viper specific ones at your Dealership. The SRT engineers spent plenty of time designing this filter and it comes from intensive study and results from racing and other venues. Won't cost anymore than a Mobil 1 or K&N and frankly it is designed for the flow characteristics and g loads of the Snake.
If you have a black MoPar filter on your car, it is not Viper specific , though it will fit on the Gen I thru Gen IIIs. All your large Viper Dealers will carry the proper ones, along with our good buddy Chuckie T., and there is a filter only for the Gen IVs.
Bill Pemberton
Woodhouse