Talk with most experienced off-road enthusiasts and they will recommend that you air down your tires while off road. Airing down increased the contact patch of the tire and allows it to better conform to the contact surface. People will recommend anywhere from 8 to 10 psi to 20 psi. When you go real low you have a higher risk of the tire bead becoming separated and loosing all pressure. I run my tires between 18 and 24 psi when off road.

The problem that his presents is what to do when you get back on the blacktop to run at highway speeds. Keeping your tires aired down is not safe. The tires have a tendency to run MUCH hotter and the stability of the vehicle is compromised. For me I chose to add a CO2 system to my FJ Cruiser to be able to air the tires back up.

With high end systems being out of my price range I chose to go with Ultimate Air.

The Ultimate Air system came with a solid tank mount, regulator, hose and air chuck. I chose to mount my tank in the back of the Toyota FJ Cruiser in the vertical position.

In the rear left is the perfect location for the air bottle. Utilizing the bolts for the bag hangers I attached an aluminium plate that I was then able to bolt the air tank bracket to.

I also added a small rubber bumper a bolt at the bottom of the bracket attaching it to the plastic fender cover.

I took advantage of this mount to also add a fire extinguisher.

To help keep the clamp on the air bottle shut I place a bolt in the provided hole.

This system has served me well over the last 2 years. With the long air hose and the bottle mounted in the vertical position I never need to remove the bottle to air up my tires.I do have problem detaching the hose from the tank so I carry an air nozzle which I use to release the pressure from the host after I close the tank valve. Once I have removed the pressure the hose detaches with no problems.

One other note about having the tank in the car, you may at some point have the blow off valve pop and the tank will Loudly vent inside the car. My popped on my trip to the Maze in 2008. Luckily I was not in the FJ at the time. It was VERY loud and very startling when the tank started venting. So be aware, the tank could vent while you are driving and you will need to be ready to deal with it.