I find that there is no accessory set-up for a 1500 aux. battery even though there is a place for one. The 2500 and 3500 "kits" might work but the cost is OUTRAGEOUS! Is there an easier DIY arrangement that I can do to keep second battery "in the loop" so to speak? My owner's manual states nothing nor does my barely helpful Haynes manual. I guess an isolator will be necessary but I can't even determine what to hook up where. Thanks in advance.

 

grab one from the wrecker


do the 08 have this

 

I've added a second battery to both of my trucks. This method uses OEM parts, so it looks like a factory install. You'll spend about $300, and it'll probably take you a few hours.

TP2 aux battery install thread