Learn me about airbags (1 Viewer)

[hammerheadfistpunch]

I've been thinking about getting airbag helpers for the rear springs. Reason being that I really like my rear TJM progressive springs - great flex, great unladen ride, etc. - but they sag pretty badly under load and I do tow with it from time to time and/or put a lot of people and things in it. I has questions for those that have dabbled in this world. And no I don't want constant rate heavier springs, I'm unloaded and commute in it most of the time.

Questions -

I know you have to remove the bump stops.
Permanently (cut out) or can they be re-installed?
Are there are worries about bottoming out with the stops removed? Seems like you would have to choose between bottom-out resistance and up travel since you would need a given amount of air to prevent bottom out that maybe wouldn't allow the coils to go to full stuff. And it seems like you would change the progressiveness of the end of travel rate.

Do you get load support only (bring the ride height back to level) or ride height changes as well? I.e. if I went with independent air valving (which I would like to) can I actually change the height of one side to level it out at camp? Or lift the butt a little extra for times when departure angle is key.
Is there a good reason NOT to do independent vs connected air-lines? I realize I would have to be careful to fill them evenly most times. Alternatively, can't I just install a crossover valve that would automatically balance the pressure, then close it for ind. control?

How do they affect travel? less flex?

How reliable are the connections? I hear some people are constantly messing with them for leaks.

I feel like airbags would give me everything I want - variable load, constant ride height, camp leveling, compliant unladen ride, etc but I'm a little wary about the bump stop thing in particular.

Anyone have insights into installing these? I was looking at the Airlift 1000 from the airlift company. I was looking into their kit for full ind. control with compressor but thats probably more than I want to mess with.

 

[BILT4ME]

I've been thinking about getting airbag helpers for the rear springs. Reason being that I really like my rear TJM progressive springs - great flex, great unladen ride, etc. - but they sag pretty badly under load and I do tow with it from time to time and/or put a lot of people and things in it. I has questions for those that have dabbled in this world. And no I don't want constant rate heavier springs, I'm unloaded and commute in it most of the time.

Questions -

I know you have to remove the bump stops.
Permanently (cut out) or can they be re-installed?
Are there are worries about bottoming out with the stops removed? Seems like you would have to choose between bottom-out resistance and up travel since you would need a given amount of air to prevent bottom out that maybe wouldn't allow the coils to go to full stuff. And it seems like you would change the progressiveness of the end of travel rate.

Do you get load support only (bring the ride height back to level) or ride height changes as well? I.e. if I went with independent air valving (which I would like to) can I actually change the height of one side to level it out at camp? Or lift the butt a little extra for times when departure angle is key.
Is there a good reason NOT to do independent vs connected air-lines? I realize I would have to be careful to fill them evenly most times. Alternatively, can't I just install a crossover valve that would automatically balance the pressure, then close it for ind. control?

How do they affect travel? less flex?

How reliable are the connections? I hear some people are constantly messing with them for leaks.

I feel like airbags would give me everything I want - variable load, constant ride height, camp leveling, compliant unladen ride, etc but I'm a little wary about the bump stop thing in particular.

Anyone have insights into installing these? I was looking at the Airlift 1000 from the airlift company. I was looking into their kit for full ind. control with compressor but thats probably more than I want to mess with.

I have the Airlift bags on my LC.

I also have 2.5" heavy springs all the way around.

I DD my truck and I typically carry a 125LB wheelchair rack on the back plus about 600 LB of tools and stuff.

I have the airbags for when I load the 400 LB power wheelchair. Without the airbags, the headlights point at the sky and the weight of the wheelchair causes it to "wag the dog." Having this much load this far behind the rear axle, it is the equivalent of adding about 1000 LB above the rear axle due to the fulcrum.

I run the airbags with one line to feed both bags. It is simple this way, and the setup cost about $100 (Summit Racing) and took me about 2 hours to install. This one does NOT have the Airlift 1000 on it. I'll tell you about that one in a minute.....

I always keep at least 5 LB in the bags to keep them in place inside the springs. The rear interior bump stops are able to be removed with bolts inside them. I managed to break off one of the bolts, but no big deal, I'll drill it out when I decide I need to put them back in.

My truck is a 8/95 build as a 96 model. It had both interior bump stops as well as external frame bump stops. Some truck before and after only have the ones interior, but all of them have the holes in the frame to add the external bumps.

I have my Schrader valve inside the fuel fill door and can use a gas station compressor to quickly pump it up if I need it. I never go over 25 PSI with mine, as I will risk blowing the bags. I have kept the original stock height airbags on mine and they still work fine, as they create resistance between the coils to keep the rear up. Thee are longer bags available with the same diameter for the same price. There are other threads on this very subject and I could just tell you to search for air bags, but then I'd just be a dick and I don't feel like it ......today.

Now, on the Airlift 1000 kit. I think it's very cool. I installed this kit on my wife's 2009 Chrysler T&C for the same reason I have bags on my LC.

The cool thing with the AL1000 is that all my wife has to do is push a button on the remote controller and it pumps them up, then load the wheelchair and off we go. It is a 1 minute fill time. The kit for her van was about $1300 total and it took me two days to install it. I did have to go back in and install a "kill switch" because it is wired hot so it would keep the bags pumped all the time. Our developed a leak after about 8 months that I cannot find unless I pull out the bags and on that vehicle, I have to drop the suspension out and it's not a small task.
I mounted the pump on the interior behind the plastic fascia in the back. The pump is very audible but not noisy when driving, but it does cycle on and off while driving as it keeps the pressures equal during different conditions.

I found that during the winter, the pump cycles during the night as the temperature changes and the air shrinks, so it pumps it up to maintain pressure. I have had this system kill the battery on the van twice, hence the kill switch. It's a simple relay and a switch, so we turn it on when we're going to use it, then activate it. When we are shutting down for the night, we turn off power so it doesn't cycle. This annoys me, but I don't have time to tear into it for what I'm sure is a simple fix. There is no tank or reservoir on this system. You can do one if you like.

My wife absolutely loves the simplicity of it and believe me, if she likes it, it's a HUGE deal. I had to modify her mother's van (our can used to be her mom's and we bought it from her estate) with only 28K miles on it, and she didn't want me "butchering" her van because it will be the last "new" vehicle we'll ever own.

If I was to mount this kit in my LC, I would place the pump in the RR quarter panel (maybe use Wit's end QPM for cleaner install) and route dedicated fused wiring to the kit back there with the hoses run out the bottom of that same quarter panel. The Airlift 1000 kit keeps the lines separate and you can adjust each side separately if you choose. We run 35 PSI in the bags on the Van. I recently had a friend ask about it because the Airlift instructions he showed me stated 100 PSI. I would NEVER put that much pressure in the red addition bags, but I would in the black "pancake" bags. Mount a "kill switch" somewhere up front to kill power if needed. Otherwise it can be on 100% of the time.

Good luck!

 

[on the rocks]

I used helper bags on the rears of my 80 for 20 years. Finally yanked them, I only shaved the internal bump stops because back then I could only get one height, the frame mounted bump stops should be more than enough if adjusted right. I just got the VT's and worried they wont hold the weight I want so may go back. Never an issue off road but have 2 wheels for the extreme stuff and take it easy on the 80.
You should always run each side separate, Especially ON road, Otherwise it would worsen the body role on corners. Maybe include a valve to tie them together off road as it should help articulate and level if that makes sense,
When off- road I would also air them down to 5 PSI. Never an issue, other than an occasional leak.

Main use was a hitch haul for the motorcycle and small camper.

 

[hikermike]

Word of warning! These don't fill like tires. It takes only seconds to get to the proper pressure (at least the ones I had on my van) Don't ask me how I found out!