factory puts out 110 amps. Yes I would upgrade your alternator, if your going to be charging both at the same time its going to strain it. I'd probably go with the 160 amp. if not higher.
Man, it is going to be expensive if I half to get a new alt. A yellow top is around 250, the install and most parts will be 175 or so! J.Wal
I am going to my custom shop Monday and going to have them get me a more accurate price on everything. And I will wait on the alternator, till I think I need it. Will probably have them do the big 3 if they do my double battery. J.Wal
Wrangler NW - Dual Battery Tray Kit for F-150,Ford Expedition & Lincoln Navigator 1997-2006 edit: I see now that you have a 07