How to Install Two Batteries in Your Vehicle
- 1). Pop the hood and locate the space to mount the secondary battery tray. On the 2000 Silverado 3500, there is a spot on the core support, near the driver's side, designed to hold a second battery. Bolt the secondary battery tray in this location using the 3/8-inch ratchet and socket.
- 2). Place the replacement battery in the secondary battery tray and tighten down the tie-down strap using a 3/8-inch ratchet and socket.
- 3). Run a section of battery cable from the negative terminal on the replacement battery to a bolt on the frame, and cut it to length using the wire cutters. Strip 1/4-inch of shielding off each end of the cut cable using the wire cutters, then crimp the battery terminals onto the ends of the cut cable using the battery terminal crimper.
- 4). Bolt one end of the cable to the bolt in the frame using the 3/8-inch ratchet and socket, then bolt the other end to the negative terminal on the replacement battery using an open-end wrench.
- 5). Run the 4-gauge cable from the positive terminal of the stock battery to the positive terminal on the replacement battery, running it along the top of the core support. Cut the cable to length using the wire cutters, then strip 1/4-inch of shielding off each end of the cut cable using the wire cutters. Crimp the battery terminals onto the ends of the cut cable using the battery terminal crimper.
- 6). Bolt one end of the cable to the positive terminal on the replacement battery using an open-end wrench, then bolt the other end to the positive terminal on the first battery in the same manner.
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