I installed this back in May, but only just now got around to doing a write-up.
got herself a power upgrade - two Optima D34 Yellow top batteries
replaced the single original battery. Now the chance of having a dead battery is extremely low, even if I've been running a load with the engine off in the dead of winter.
Read on for a pictorial walkthrough of my install
Lights, compressors, CBs/radios
, and especially winches can really put a strain on a battery. The stock Jeep alternator is fairly beefy, but the battery is not so hot, and the alternator doesn't work when the vehicle is off anyway. I decided a dual-battery system would be one of my first 'big' mods. Replacing the single battery with a pair of batteries allows one to power all the accessories and with a smart battery controller it can be cut off from the main battery when the power starts to drop below cranking voltage. If someone the main cranking battery gets too low (let the regular headlights on, it was extremely cold, etc) the backup battery can be used to "self-jump start." I went ahead and upgraded from the normal OEM battery to Optima 'yellow tops' which are pretty rugged, can handle some deep discharges, and don't mind very low temperatures. Having a pair of quality batteries should mean I never need to get a jump start no matter what 'dumb' thing I do!
There are a couple different dual-battery trays for the Jeep Wrangler JK, but I went with the one from Benchmark Designs
. They are active on the forums, local, and actually care about the products they ship out - unlike some of the other 'big name' Jeep accessory companies that off-shore everything with no quality control. Of their three models I picked the one they now call 'Stage 3
' - the difference between the 3 versions is the wiring. 'Stage 1' the batteries are just permanently connected to each other, 'Stage 2' isolates the cranking battery when the ignition is off, and 'Stage 3
' has an isolator that actually monitors the voltage in the batteries and 'does the right thing.'
In this first picture we see all the stuff included in the tray package. There are three categories if items - the big tray in the middle, the wiring (the silver 'thing' on the top shelf and the wires on the bottom), and support pieces (everything else).
The yellow tops[/url]
. They have an interesting design where you remove the handle, and then remove the protective cap, then the cap can connect in two different ways to the bottom of the battery to fit your mount. These things are stupid-heavy, be careful when lifting them - since I was lifting them higher than my chest and then out and then down in to the engine bay I ended up straining my back for a week. The weight also means you really have to pay attention when buying them online - a good deal might be horrible when you discover the shipping fee.
Here is a picture of the stock battery layout. The thin red wire coming from the edge of the body is temporary wire for my CB
. All the others (green, multiple black, multiple red) are what comes from the factory. That flat silver braided line is a ground strap connecting to the metal hood.
is lifted (]3.5 inch Teraflex) and has larger (35 inch) tires so I needed to pull out my work platform to stand on.
Gotta love the rugged engineering of the Jeep! Instead of using the hood prop rod, I folded a beach towel, put it on the top of my front windshield, and put the hood all the way back. Since we'll be working way up near the hinges this is very helpful. You get way more light, more elbow room, and you don't whack your head constantly.
The instructions that came with the kit were very good, and had b/w pictures in them, so I won't be covering every single step in detail, just an overview with some larger color pictures and some personal comments that hopefully help whoever finds this in their search.