I think it's a group size 24 battery, but a group 75 or 78 dual terminal will work. Do you have any belt squealing when the battery light comes on? My battery light has come on twice since I've owned my truck. First time the belt was loose, second time the alternator blew. If it is the alternator and you have a KA24E, I suggest getting an alterator for a 1998 frontier 2.4 because it's cheaper and 10 amp more capacity thana stock replacement. I have one on my 96.
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