The Airaid # AR523-284 you were looking at for your 2013 Nissan Armada is actually an open air system, because the unit is not fully encased.
The main advantage that the open box systems have over the enclosed box system is that open systems offer the maximum amount of airflow. The enclosed box systems will still have plenty of air flow, just not as much as an open box system. The closed air systems will look like the picture I have linked to this page for your convenience.
Another main... view full answer...
Yes, the 6 bolts and washers are included with the Curt trailer hitch fits the 2008 Nissan Armada, part # 13188.
I've linked the install details and an install video we did on a 2010. The process is the same on your 2008.
If you're going to be towing with the Nissan and need trailer wiring as well the 4-way I recommend to power the trailer's lights is part # C59496.
Then for a ball mount we have a kit that might work for you part # 989900. view full answer...
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