Rear Air Bags for 100

[Adam R]

I just found this board the other night and have wasted (spent) several hours for the past few nights reading every post. My wife has a '99 LC and I have a 01 Jeep TJ that has been heavily modified. I've read quite a bit of negative feedback about the use of airbags and how they adversely affect articulation, etc.

I've been running airlift bags in my TJ for about 3 years with no problems. I run about 7 lbs when empty. Empty means about 200 lbs of gear in a custom wooden box where the rear seats would be in a TJ and a 315/75-16 spare hanging off of a custom tire carrier in back. Total weight is just under 5000 lbs in this configuration. I will pump them up to 20 lbs if I put on the receiver hitch tray and put 300 lbs on it for cross country / freeway driving or if I tow something with it. It rides awesome and keeps the TJ headlights pointed down versus into the eyes of oncoming trucks. Truckers seem to have no problem letting you know if your headlights are bothering them.

Off road, they go back to 7 lbs and I've run every 4+ trail in Moab plus Pritchetts Canyon with zero problems. Plus, you can't easily bottom out the suspension with the bags inflated to 7 lbs. I haven't found it to adversly affect articulaton at all since the bags are plumbed to one another.

Has anybody put air bags in and which model numbers fit for 2 or 3 inch lift coils in a 100 LC.

Thanks,

Adam R.

 

[Augie]

I had airlift 60755 (the tallest bag in the diameter that would fit stock spring, but don't qoute me on that) for about 3 years and 2 years with OME 665. It took some time to figure out the right pressure for a certain condition.

The progressive spring design are a bit confusing with the airbag. My truck at 15 PSI would handle like a boat and spring felt very soft. With the bag at 35 psi it would do a very bad stink bug and lift the rear end another 3-4" above standard (2-3" taller thand OME 665 and would handle really well down the road. I fully deflated mine for on road. Run 25-35 PSI fully loaded and run 10-15 PSI for off road clearance. Aticulation does not seem to change since the shock is the limiting factor anyway.

I also run mine with an inline ball valve to isolate left and right pressure. I could really feel the stability difference with the valve open or closed. I run mine open off road so they would not hamper articulation.


This progressive spring design really screw up my OME shock. This is one application where Bilstein would be a much better solution. I really want to get ATS4X4 custom Bilstein shock when Slee starts carrying them.

 

[Adam R]

When I sized my air bags for the jeep, I found a bag that was the same internal diameter as the spring and about 1 inch taller than the space available when my jeep was sitting level or empty, basically my normal driving configuration. That way it acts as a true helper spring. It sounds like you may have way too much (tall) of a bag and you are using air for the first part of your suspension compression before the springs begin to work.

At 10 lbs of pressure, I only get about 1/2 inch of lift and at 50 lbs, I only get about 1.5 inches of lift. My rear springs are 4 inches taller than stock and my air bag is 7 inches tall if I remeber correctly.

Even with 500 lbs of "extra stuff" behind the rear alxe on the jeep, it rides great and sits level. Without the bags, the rear drops several inches which radically changes the headlight pointing on a short wheel base jeep.

Adam R.