Now that the dual battery mounting tray is installed, the next step is installing the battery's and connecting the wires.
Install the two battery's with the posts facing outward.
Connect the J bracket on both sides and mount the hold down bracket.
Next install the smart isolator. NOTE: The isolator has 3 wires, but the only one used is the black that goes to chassis ground.
Since I have a ton of accessory wires, I installed a power buss-bar. Buss-bars help keep the wires somewhat organized and away form the battery terminals where they can cause corrosion. These are available at various locations. I found mine at a boat supply house.
Reconnect the evap Purge solenoid. Note it should be mounted somewhat upright. I wire tied it to a wire bundle. The OEM bracket was removed with the battery tray.
Do a last check to verify that all connectors are connected and the wires are connected properly.
Here's a final pic of my install.
Conclusion
The dual battery project was a rewarding experience. I highly recommend this for anyone that has added accessories that require direct battery connectivity.
The step of the dual battery project is reassembly. The Benchmark design guys have this project nailed. The fit and finish of their parts is outstanding. Everything fits perfectly with no modifications whatsoever.
Reassembly
The first step is cutting the T piece of the firewall insulation. This step needs to be completed so the new battery box fits securely to the firewall.
Next, mount the battery tray with the three washer nuts. Do not fully tighten them yet. The tray is perfectly sized and slides right in with minimal effort.
Then connect the fender well screw
TIPM bracket install
Benchmark Designs engineered the TIPM module mount well. It is a separate part that bolts onto the main tray with two screws. This is a nice design because it keeps the try small and easy to manage when installing and it keeps the top of the shock absorber exposed (more on why that is important in a minute).
To start, mount the original TIPM bracket to the mount. This is keyed so the bolt holes only line up in the right direction.
Next is a bit of an unusual step, but required. The Benchmark tray is supporting two very heavy battery's. The forward driver side corner is a weak point. Benchmark cleverly took this into account by creating a straight bracket that is bolted through an existing hole in the passenger shock tower. The other end connects to the tray making a very strong structure.
Getting to the hole in the shock tower to mount the bolt, however, is not easy. It is behind the shock. I have large OME shocks and there is no way to get behind them. This actually became an easier task than I expected. I found it was easier to install the bottom bracket by removing the top bolt of the shock before installing the TIPM mount. Thanks to Benchmark's separate TIPM tray, this keeps the area clear with easy access.
Shock with top bolt removed.
With the shock lose at the top, there's just enough room to bolt on the bracket. .
Next, you reinstall the shock, mount the TIPM tray and connect the top of the straight bracket to the tray.
At this point the battery box is installed. However, we still have to deal with the factory air filter mount that we removed. The way Benchmark Designs handles this is by cutting the air filter mounting bracket from the large battery box assembly. I was a bit skeptical of this, but it worked perfectly. After cutting, just mount it back in the same location.
Next reinstall the power steering fluid holder and install the factory air filter enclosure.
The final step is to make sure all nuts and bolts are tightened. At this point, the battery box is mounted! Next up is connecting the wires and installing the battery's.
Most modified Jeeps can quickly overtax a stock electrical system. Winches, lights, audio systems, etc. put a bigger load on the system than what it was designed for. A power spike from a winch or turning on powerful lights can easily damage the sensitive electronics. Notwithstanding the fact that everything has to be connected to the battery, which makes it a rats nest of wires. I've added quite a bit to my Jeep at this point. A clean up in the battery compartment was in order. A dual battery system will take care of the power surges and clean up wiring, so I decided now is the time to tackle this project.
Unfortunately, Chrysler doesn't offer a dual battery option for Jeep. It's up to the owners to figure out how to do it. There are a few after market vendors that sell dual battery kits for the Wranglers. I did a ton of research on which one to buy. My research always pointed back to Benchmark Designs. They are a small mod company in Seattle, Washington that doesn't make a lot, but what they do make is excellent. I decided to go with their Dual Battery tray and added a smart battery isolator. The battery setup I ordered isn't listed on their website, but it is basically the KISS system with a a different battery isolator. You can contact John Carruthers at Benchmark (425.417.7372) if you want to order the upgraded system.
Disassembly NOTE: This is one of those projects that requires an solid understanding of electrical wiring. Care must be taken throughout this project. One shorted wire could blow the Jeep computer or damage who knows what. You have been warned....
The first step is pulling the battery and getting the wiring out of the way:
Remove the electrical connector from the Evap Purge Solenoid
Remove the connector from the top of the battery box
Remove the battery and push the cables toward the engine and out of the way.
The next step must be done with care. You need to disconnect the TIPM module (fuse box). The only wire connector that you need to disconnect is the one on the outside facing toward the rear of the Jeep. Do NOT disconnect the connectors under the TIPM module!!
Then you need to remove the 4 10MM screws that hold the TIPM mounting bracket.
I don't have a good picture of this step, but you need to remove the factory air filter housing. This is easier than it looks. It is mounted with rubber feet. It pulls straight up and out. You just need to disconnect the intake tube coming from the engine.
Now it's time to remove the entire battery box assembly. It connects to the firewall with 3 washer nuts and goes to the front of the engine compartment. This is one big piece of plastic. To make removal easier, remove the power steering fluid tank first. It is removed with one bolt.
Remove the 3 washer nuts on the firewall, then disconnect the fender nuts, finally remove the bolts that were under the air filter.
Finally, you just have to remove the box. It is easy, but you have to be careful. It is easy to scratch the paint or cut a wire. Start by lifting in the front then twisting a bit. It will come right out.
Here's what it looks like with the box removed. Lots of space!
After installing the ExpeditionOne rear bumper w/tire and carrier, my Jeep started to sag in the rear. This was expected since I added over 200 LBS back there ;-) To level it out, I needed to add about 1" of lift to the rear. I did this by installing TeraFlex 1" Coil Spacers with integrated spring retainers.
The trackbar and suspension is already setup on my Jeep, so I was able to do this project without pulling the entire rear end apart. I used jacks, stands and coil spring compressors to save me time. This is basically the same process that would be used if installing a leveling kit.
The first part of the project is jacking up the Jeep and securing it on stands. Having a tall jack makes this job easier. If you can get it high enough, you can do this project without removing the tires.
Stock Jeep Spacer above coil
After securing the body of the Jeep on jack stands, I kept the axle fully compressed with a jack on the center gear housing (pumpkin). This helps keep the springs compressed as much as possible making the spring compressing job a bit quicker. I then installed spring compressors on opposite sides of the spring and slowly tightened them in evenly alternating sides.
NOTE: It is very important to go slow and keep the sides even. The springs hold substantial energy and can kill you or significantly damage the Jeep if a compressor slips off or breaks.
Spring compressor on Coil
Stock coil spacer removed
The next step is to remove the coil from the axle, install the 1" TeraFlex spacer in the stock location and reinstall the coil by slowly releasing tension from the spring compressor on both sides evenly.
I started on the drivers side and then worked to the passenger side. The only difference is the fuel tank is somewhat in the way on the passenger side, which made it a bit more challenging to compress the spring.
Before spacer height 39"
After TeraFlex 1" Spacer Install - 40"
Spring spacers are the quickest and easiest way to add .5" to 2.75" of lift to a Jeep. The only thing to be cautious of is shifting the axle to body alignment. The best way to address axle alignment is by installing adjustable front and rear trackbars.
The final product is just a slightly forward stance (rake). The front is 1/4" lower than the rear. I prefer a bit of a rake in the Jeep. I tow a heavy trailer and it keeps the Jeep level when I load it up in the rear. It also helps with on-road stability by shifting some of the weight forward on the front wheels.
Larger tires have a tendency to wonder around on the road and can cause bump steer when on the trail. This ia a quick and easy fix. Just have to install a heavy duty front stabilizer shock. This is a simple project -- two 18MM bolts need to be removed and a new shock installed. I chose TeraFlex to keep my suspension with the same company in case I ever have issues, but there are many after market options out there.
Original Steering Stabilizer
TeraFlex Steering Stabilizer
This is about as easy as it gets. When I get a bit more time, I will be installing a Woods Steering Stabilizer Relocation bracket. This will move the shock above the trackbar giving it a bit more protection from the trail.
Living in Chicago I find it necessary to use my horn more than I'd like. Cars pull out in front of me, people walk in the middle of the street like it's their back yard, etc. Sadly, when I honk at them they either ignore me or laugh at my big bad Jeep that sounds like a Scooter. I have been emasculated for the last time. I'm installing a real horn!
When researching horns I found that there's not as much out there as I expected. There are a ton of air horns and cheap after market horns, but most won't fit in the tight space under the hood or aren't attention getting. I decided to go with a PIAA Sports Horn. They have two different versions. The lower pitched 400hz/500hz and the high pitched 500hz/600hz. I listened to as many sound clips as I could find online and decided to go with the low pitched horn. It has a deep full note that sounds more masculine. The high pitched horn seems to be more appropriate for a Porsche or sports car.
The stock horn is located on the drivers side just behind the headlight. It is held on with one torx screw.
After dismounting the horn you'll find two wires connected to it. The black one is negative and the yellow/brown is positive.
NOTE: the OEM and PIAA horns are not polarity specific. You can wire them either way and it will work fine. However, Air Horns and some other after market horns may be. Read the directions!
Since the PIAA horn is a set of two, I had to create a jumper wire to accommodate the connections to the second horn. The easiest way to do this is with wire-tap connectors that are available at Radio Shack.
The next step is to crimp insulated spade connectors on the other end of the wire that are also available at Radio Shack. The horns will be mounted somewhat close, so the wire only needs to be about 8" in length.
Space is limited in a Jeep. It is especially difficult to mount anything under the hood that will be off-road worthy and maintain the stock look. Fortunately I found a lower bolt that holds a probe of some-sort. I used that location to mount the 500Hz horn. The install is simple. Remove the bolt, connect the original wires to the horn, and put it back together.
The 400Hz horn will not re-mount in the OEM location. The horn is a bit too big. I was able to use the bolt that mounts the remote start hood safety switch.
Pictures don't do this install justice. I created this YouTube video that has sound clips of the original Jeep JK Wrangler horn and the PIAA horn. Can you hear me now? ;-)
