(Full disclosure: this is a long-term review of the first-generation Genesis dual-battery kit for the 2007-2021 Tundra. It has been superceded by a later design, the merits of which I cannot address.)
In 2021 we bought a beautiful, 80-year-old cabin in Fairbanks, Alaska, and soon realized we’d need a dedicated vehicle to leave there. A full-sized 4×4 pickup seemed the right choice, both for the conditions near the Arctic Circle and because I’d be hauling up a cargo trailer loaded with furniture, tools, and other immediate needs. So we bought a hideously overpriced (it was that period) 2014 Toyota Tundra.
Since we fully intended to do a lot of exploring, and since we also intended to spend part of our winters there (so as not to be viewed as mere un-snowbirds), I considered it mandatory to install a dual-battery system. I wanted the kit to fit in the engine compartment if at all possible, for simplicity, and the only one that came up on searches was from Genesis Off Road. At that time, in early June of 2022, I planned to drive up within a couple of weeks, so I ordered the kit with little in the way of research into it, or even a thorough reading of the installation procedure. Mea Culpa.
The first revelation when I got the kit and read the instructions was that it required Optima batteries, each of which was smaller than the stock battery. Starting reserve capacity would be reduced in comparison to the full-size stock battery, and the specified deep-cycle Yellow Top Optima had a capacity of just 48 amp-hours. Neither is ideal in potential -40º conditions. Ah well—I figured that was the sacrifice necessary to fit two batteries in the stock location.
The battery tray and top were nicely made, powder-coated, clearly laser-cut and incorporating a fancy large-cat-head design. The control unit looked solid, and all necessary wiring was already in place. Reading installation instructions thoroughly at last, I was a bit perturbed to discover that the entire assembly attached to the bottom of the original battery platform with four Rivnuts. That seemed a bit light for 60-plus pounds of battery, mount, and charge controller. The next thing I noted was that all the included hardware, including the bolts that secured the top plate to the base, was SAE. Really? On a Toyota? That might have saved Genesis, what, 50 cents per kit over metric hardware? A small thing, perhaps, but annoying.
