392 & Diesel Wrangler Dual Battery System - Under Seat
Description
Under Seat Dual Battery Power for Wrangler 392 & Diesel JL
This Genesis Offroad Gen 3 dual battery system mounts the auxiliary battery under the rear seat and uses a smart Power Hub to manage charging, so your accessories run from the Aux battery without draining your cranking battery.
Smart Gen 3 Power Hub
The heart of the kit is a smart battery combiner that connects and disconnects the batteries automatically. When the engine starts, it charges the cranking battery first, then links both batteries in parallel so the alternator can charge them together. When system voltage drops below approximately 12.7 volts for about a minute, the combiner separates the batteries so accessories on the bus bars continue to run from the Aux battery while the cranking battery stays ready to start.
Bus Bars for Clean Accessory Wiring
Integrated positive and negative bus bars make adding electrical accessories simple. Three stud sizes handle heavy cables for gear like a winch, air compressor, stereo amplifiers, or fuse boxes, while #10 screws accept smaller ring terminals for low amp accessories such as small LED lights.
Battery Size Options Under the Seat
The stock batteries remain under the hood while the new Aux battery sits under the back seat in adjustable brackets. The battery needs to be approximately 6.8" deep. Commonly used sizes include Group 35, 34R, and 94R, with Group 27F as the largest battery that will fit. The 27F offers high capacity but is a very tight fit; a 94R is almost as capable and easier to install, especially on the 392.
Heavy Duty Cables
The kit uses 2 gauge heavy duty high strand count pure copper welding cable. Welding cable is more flexible and more conductive than standard battery cable and has a thicker abrasion resistant jacket for long term durability. Pure copper lugs are tin plated for better conductivity and corrosion resistance, then sealed with extra thick adhesive lined heat shrink to protect the cable ends.
Installation and Compatibility
If you are handy with basic tools and follow the detailed installation video, most driveway installs take about two to three hours. Many 4x4 shops bill around two hours on a stock vehicle, with additional time if existing wiring needs to be rerouted to the bus bars. This kit mounts the Power Hub under the rear driver side seat, and the seat back will fold down only about halfway. If you need the rear seat to fold fully flat, consider the version that mounts the Power Hub under the hood. This under seat kit can also be installed on a gas engine Wrangler JL.
Specifications
- Vehicle Fitment: Jeep Wrangler JL 392 and diesel
- System Type: Gen 3 dual battery system with smart Power Hub
- Aux Battery Location: Under rear seat on driver side
- Battery Size Range: Group 35, 34R, 94R, and Group 27F Aux battery (6.8" deep)
- Bus Bar Stud Sizes: 3/8", 5/16", and 1/4" studs plus #10 screws for small ring terminals
- Cable Type: 2 gauge high strand count pure copper welding cable with tin plated lugs and adhesive lined heat shrink
- Typical Install Time: Approximately 2–3 hours for DIY or around 2 hours at a 4x4 shop
- Power Hub Location: Under rear seat; seat back folds about halfway down
Partner item — ships directly from Genesis Offroad
Description
Under Seat Dual Battery Power for Wrangler 392 & Diesel JL
This Genesis Offroad Gen 3 dual battery system mounts the auxiliary battery under the rear seat and uses a smart Power Hub to manage charging, so your accessories run from the Aux battery without draining your cranking battery.
Smart Gen 3 Power Hub
The heart of the kit is a smart battery combiner that connects and disconnects the batteries automatically. When the engine starts, it charges the cranking battery first, then links both batteries in parallel so the alternator can charge them together. When system voltage drops below approximately 12.7 volts for about a minute, the combiner separates the batteries so accessories on the bus bars continue to run from the Aux battery while the cranking battery stays ready to start.
Bus Bars for Clean Accessory Wiring
Integrated positive and negative bus bars make adding electrical accessories simple. Three stud sizes handle heavy cables for gear like a winch, air compressor, stereo amplifiers, or fuse boxes, while #10 screws accept smaller ring terminals for low amp accessories such as small LED lights.
Battery Size Options Under the Seat
The stock batteries remain under the hood while the new Aux battery sits under the back seat in adjustable brackets. The battery needs to be approximately 6.8" deep. Commonly used sizes include Group 35, 34R, and 94R, with Group 27F as the largest battery that will fit. The 27F offers high capacity but is a very tight fit; a 94R is almost as capable and easier to install, especially on the 392.
Heavy Duty Cables
The kit uses 2 gauge heavy duty high strand count pure copper welding cable. Welding cable is more flexible and more conductive than standard battery cable and has a thicker abrasion resistant jacket for long term durability. Pure copper lugs are tin plated for better conductivity and corrosion resistance, then sealed with extra thick adhesive lined heat shrink to protect the cable ends.
Installation and Compatibility
If you are handy with basic tools and follow the detailed installation video, most driveway installs take about two to three hours. Many 4x4 shops bill around two hours on a stock vehicle, with additional time if existing wiring needs to be rerouted to the bus bars. This kit mounts the Power Hub under the rear driver side seat, and the seat back will fold down only about halfway. If you need the rear seat to fold fully flat, consider the version that mounts the Power Hub under the hood. This under seat kit can also be installed on a gas engine Wrangler JL.
Specifications
- Vehicle Fitment: Jeep Wrangler JL 392 and diesel
- System Type: Gen 3 dual battery system with smart Power Hub
- Aux Battery Location: Under rear seat on driver side
- Battery Size Range: Group 35, 34R, 94R, and Group 27F Aux battery (6.8" deep)
- Bus Bar Stud Sizes: 3/8", 5/16", and 1/4" studs plus #10 screws for small ring terminals
- Cable Type: 2 gauge high strand count pure copper welding cable with tin plated lugs and adhesive lined heat shrink
- Typical Install Time: Approximately 2–3 hours for DIY or around 2 hours at a 4x4 shop
- Power Hub Location: Under rear seat; seat back folds about halfway down
Partner item — ships directly from Genesis Offroad
