ARB Single Compressor Overview & Installation with the Shrockworks Mount Bracket
There are many dual batteries and onboard air compressor options available for a 5th Gen 4Runner.
Shrockworks, Genesis, C4 Fab, Sponsored by Wifey, DIY and the recently installed compressor with Slee bracket are all options for setting up a second battery or air compressor in your rig. It can get a little overwhelming when making the decision.
All the compressor mounts have a unique way of setting up their systems and it depends on how many other accessories you have, and where they are located, in order to determine which mount to choose.
Some of the other main factors may include a secondary battery, a larger intake, or even a switch panel.
There are two choices when it comes to where to mount the second battery. Either battery mount options belong on the passenger side. The first option is against the firewall (closer to the cabin) or directly over the air injection pump (closer to the 4Runner grille).
Each of these has pros and cons and both decisions may influence where your air compressor is installed. Some research, vision and ultimately preparing for the future of your build will help select the appropriate setup.
- UPDATE: Shrockworks is no longer in business (Jan 2023).
- For similar products, you can check out the guide to compressor brackets or see our compressor and switch brackets post.
Shrockworks Air Compressor Mount & Air Pump Relocation
Most kits utilize the passenger rear area under the hood for the second battery.
I initially had some concerns about the weight riding back there without solid reinforcement. Most people get by just fine putting the second battery in that rear location. I’m more of a “what-if” guy.
Choosing to keep it opposite the starting battery was an easy decision due to that area being a mirror image of the driver side. On the 5th Gen 4Runner, the smog pump is currently located there.
Another obstacle to tackle. I ultimately went with Shrockworks for their battery/ACR mounting tray, as well as their use of the forward portion of the engine compartment for the secondary battery. There are three options when choosing the kit.
There is the standard kit to relocate the pump, another option for an aftermarket washer fluid tank (definitely a good option for high clearance bumpers) and a single ARB compressor mount that will adapt to the standard smog pump mount plate. I had previously purchased a single compressor that I was initially going to mount on the driver side under the hood.
I ultimately went with the ARB mount because it utilizes the space that would normally be empty.
Smog pump relocation
Shrockworks supplies all hardware needed to install the new mount in the rear of the engine compartment, as well as all of the necessary hardware/fittings for modifying the existing smog pump hoses to route to the new location.
The directions do call to remove the airbox from the vehicle. The smog pump harness extension is routed under the airbox from the factory location. In total it took about two hours for a complete install.
Nothing too difficult and the directions were spot-on. No ingenuity required.
*Disclaimer: I did not plumb the smog pump the same way Shrockworks specifies in the directions.
My issue was with a small amount of rubbing on the rear airbox lid clip. I may have cut the hose to the wrong measurements.
Not completely sure.
In any case, it was rubbing more than I am comfortable with. I went to the local auto parts store and bought two ¾” elbows and about a foot of ¾” hose. I cut and fit a new route for the hose to avoid all the rubbing.
This part is pretty straight forward.
Once the smog pump is located to the rear, this area is now open for business.
There are two minor adjustments that need to be made before the tray sits perfectly:
- First, the AC line mounting tab will need a 90-degree angle bent into it in order to bolt onto the new battery tray.
- Second, Shrockworks set up the secondary battery tray to perfectly mount the power steering reservoir in the near stock location.
After those two tasks are complete, it’s all downhill from there. The new battery tray liner is included to protect the bottom of the battery from the mounting bolts for the battery tray.
Mounting the compressor can be done before or after the smog pump mount is installed.
It utilizes the standard mount on the compressor. Four locknuts secure it to the new mount. The mount has studs welded onto the mount that line up perfectly with the compressor mount. Wiring the compressor was the only complicated part of the entire process. Mostly due to my lack of familiarity with the compressor.
The compressor comes with a relay and switch built into the harness. I run a sPod to control most of my accessories, including the compressor.
I initially figured the relay in the sPod would serve the same purpose. Not exactly. After realizing my error, I hooked the compressor to the battery and the switch ends to the sPod.
Shrockworks made provisions on the backside of the mount for the relay to be securely mounted. As you can see below, I routed the harness along the upper firewall to maintain access to the fuse located directly in the middle of the power cable.
Do yourself a huge favor and take your time.
Most mounts under the hood are pretty sharp and will eat through the wires quickly if not secured properly. A few minutes will save a huge headache on the trail.
The construction and workmanship of the mount are top-notch.
Manufactured from heavy gauge stainless steel and plenty strong to support the ARB compressor for years to come. I have zero regrets about going with this compressor mount because it solved two problems for me.
One, I wanted the second battery in the front of the engine compartment. Second, I wanted an onboard compressor. It’s very clean and highly functional.
I couldn’t be happier with the way it turned out.