Growing up doesn't have to suck

[Rocket Man]

I don't see air bags helping much with your issue of oscillation. They're springs, just like coils, so they can squish and unsquish just the same. You need damping, so shock absorption should be your focus.

I've been pondering the PSI thing lately. The way I'm currently thinking, Airlift makes a bag that is inflated to lift and level a loaded vehicle, and does so with a max of 35PSI. I don't know what PSI the factory air sleeves get to lift the Tahoe. I've read that the compressor is capable of 135+PSI, but that doesn't necessarily mean that it's gonna push that amount of pressure into the air sleeves. The system is triggered by position sensors and not PSI, so that's the savior here. I think it's simply that the Airlift bags are multiple times bigger than the air sleeves, so they can lift with a lower pressure, but just require more volume.

So, the compressor may actually work about the same or less amount. It'll run a little longer trying to fill a larger volume, but it's only gonna need to pump them up to ~35PSI (probably as a near-max, too) to get the same amount of lift that the smaller sleeve bags do but at a much higher PSI.
Unless I hear something that stops me in my tracks, I'm just gonna go for it and see what happens. I'm currently shopping replacement compressors and hope to have one ordered for this weekend.

The compressor is built for low volume, high pressure. Notice the ID of the air lines- tiny tiny. It runs 1/8” lines which won’t inflate something as big as airlift bags unless it runs forever. I’m not sure what CFM the compressor is capable of but I’m pretty sure you’re going to be frustrated waiting for the bags to fill.

 

[kbuskill]

I don't see air bags helping much with your issue of oscillation. They're springs, just like coils, so they can squish and unsquish just the same. You need damping, so shock absorption should be your focus.

I've been pondering the PSI thing lately. The way I'm currently thinking, Airlift makes a bag that is inflated to lift and level a loaded vehicle, and does so with a max of 35PSI. I don't know what PSI the factory air sleeves get to lift the Tahoe. I've read that the compressor is capable of 135+PSI, but that doesn't necessarily mean that it's gonna push that amount of pressure into the air sleeves. The system is triggered by position sensors and not PSI, so that's the savior here. I think it's simply that the Airlift bags are multiple times bigger than the air sleeves, so they can lift with a lower pressure, but just require more volume.

So, the compressor may actually work about the same or less amount. It'll run a little longer trying to fill a larger volume, but it's only gonna need to pump them up to ~35PSI (probably as a near-max, too) to get the same amount of lift that the smaller sleeve bags do but at a much higher PSI.

Unless I hear something that stops me in my tracks, I'm just gonna go for it and see what happens. I'm currently shopping replacement compressors and hope to have one ordered for this weekend.

The air bags wouldn't help with the oscillating BUT they would allow me to keep the auto leveling feature while running the Rancho 9 way adjustable shocks, in place of the current air shocks, to control the oscillating. The setup described would keep me from trying to figure out how to run a dual shock setup on each side.

 

[iamdub]

The air bags wouldn't help with the oscillating BUT they would allow me to keep the auto leveling feature while running the Rancho 9 way adjustable shocks, in place of the current air shocks, to control the oscillating. The setup described would keep me from trying to figure out how to run a dual shock setup on each side.

Ah. I'm tracking now.

Even after Mark's post and valid points, I'm still gonna press on and be a Guinea pig. I was hoping for some feedback about the compressors but haven't had any replies to my thread. I'm ordering one tonight- either the Cardone or Dorman. Gonna do a little more research and reflecting...

 

[iamdub]

The compressor is built for low volume, high pressure. Notice the ID of the air lines- tiny tiny. It runs 1/8” lines which won’t inflate something as big as airlift bags unless it runs forever. I’m not sure what CFM the compressor is capable of but I’m pretty sure you’re going to be frustrated waiting for the bags to fill.

I definitely noticed cuz I was planning on gluing the factory air line inside the Air Lift air line! lol

Any idea on how long, on average, the OEM setup runs at start-up? I'd like to say that I can be patient since I rarely drive it and I always let it idle for a few minutes before I take off. I also rarely ever tow. My main point for keeping the system is that I'm planning on the drop springs to be much softer than the stock ones as well as yield a little more drop than I'm wanting. I want to use the air to both pick it up to the height I want and put the spring rate where I want it. Sitting level when parked/"aired out" and slightly raked when driving would be ideal for me. Having it automatically lift when loaded and/or towing is a cool side benefit, although one that will rarely ever be utilized.

I have an old Viair 380c and 3 gallon aluminum tank that I'd love to tuck in the factory compressor's place. Incorporating the dryer, exhaust valve and other electronic controls would be the hurdle. But I can look at my roached original one to see if I can come up with anything.

 

[Rocket Man]

I definitely noticed cuz I was planning on gluing the factory air line inside the Air Lift air line! lol

Any idea on how long, on average, the OEM setup runs at start-up? I'd like to say that I can be patient since I rarely drive it and I always let it idle for a few minutes before I take off. I also rarely ever tow. My main point for keeping the system is that I'm planning on the drop springs to be much softer than the stock ones as well as yield a little more drop than I'm wanting. I want to use the air to both pick it up to the height I want and put the spring rate where I want it. Sitting level when parked/"aired out" and slightly raked when driving would be ideal for me. Having it automatically lift when loaded and/or towing is a cool side benefit, although one that will rarely ever be utilized.

I have an old Viair 380c and 3 gallon aluminum tank that I'd love to tuck in the factory compressor's place. Incorporating the dryer, exhaust valve and other electronic controls would be the hurdle. But I can look at my roached original one to see if I can come up with anything.

The OEM only runs a few seconds at start up but that’s just to top off the airbags in the shocks which are tiny in comparison to the airlift bags. They’re completely different animals. Airlift hold way more air and operate at low pressure. You would be better off wiring the Viair into the place of the stock compressor but I’m not sure how that would work. You need more volume somehow. If you use the stock compressor to fill the airlift bags I would expect 15 -20 minutes or maybe more of run time if the comp doesn’t burn up first.

 

[iamdub]

The OEM only runs a few seconds at start up but that’s just to top off the airbags in the shocks which are tiny in comparison to the airlift bags. They’re completely different animals. Airlift hold way more air and operate at low pressure. You would be better off wiring the Viair into the place of the stock compressor but I’m not sure how that would work. You need more volume somehow. If you use the stock compressor to fill the airlift bags I would expect 15 -20 minutes or maybe more of run time if the comp doesn’t burn up first.

Geeeeez. I was thinking it ran for 20-30 seconds to top off the stock bags and was guessing the Air Lifts to be about 5 times the size, leading to 2.5 minutes run time at most.

I'm gonna need a functioning compressor, dryer, exhaust valve, etc. regardless of what I do so I guess I should bite the bullet and order one. It can hang out with the fuse pulled for all I care while I cannibalize my original one. Connecting the factory stuff may not be so bad. It'd probably be more a matter of adapting the Viar and tank's output size to the factory compressor lead hose and exhaust port sizes.

 

[Rocket Man]

Geeeeez. I was thinking it ran for 20-30 seconds to top off the stock bags and was guessing the Air Lifts to be about 5 times the size, leading to 2.5 minutes run time at most.

I'm gonna need a functioning compressor, dryer, exhaust valve, etc. regardless of what I do so I guess I should bite the bullet and order one. It can hang out with the fuse pulled for all I care while I cannibalize my original one. Connecting the factory stuff may not be so bad. It'd probably be more a matter of adapting the Viar and tank's output size to the factory compressor lead hose and exhaust port sizes.

The stock shocks have a tiny bag that surrounds the shock itself, you have to keep in mind that inside those stock bags are a complete shock assembly that takes up most of that room. They’re not “real” air bags like on a bagged vehicle. That’s why you can still drive on them after the bag blows. They just don’t adjust up and down anymore but the shocks are still there.

 

[iamdub]

The stock shocks have a tiny bag that surrounds the shock itself, you have to keep in mind that inside those stock bags are a complete shock assembly that takes up most of that room. They’re not “real” air bags like on a bagged vehicle. That’s why you can still drive on them after the bag blows. They just don’t adjust up and down anymore but the shocks are still there.

Right, it's a rollover sleeve. I was just looking at mine (since I have an inside view due to the complete separation ) and there's maybe 1/4" air space between the inside and outside walls. There's obviously very little cylindrical volume on top as well. Now that I've put eyes on it better, I'd say the comparison, using fluid volume, is more like 1 cup in the OEM sleeves and 2 quarts in the Air Lift bags, which is 8 times the volume. Again, these are very rough figures, but probably conservative so the difference is probably larger.

I couldn't decide if the Cardone was any different than the Dorman, so I aimed for the middle and the most popular with 600+ 5-star reviews and ordered the Dorman. I also ordered a new air line kit for the Air Lift bags so at least I'll be able to use them manually. Maybe I should order a bicycle pump to keep in the factory jack compartment in case I'm away from home and need to pump up.

 

[Rocket Man]

Right, it's a rollover sleeve. I was just looking at mine (since I have an inside view due to the complete separation ) and there's maybe 1/4" air space between the inside and outside walls. There's obviously very little cylindrical volume on top as well. Now that I've put eyes on it better, I'd say the comparison, using fluid volume, is more like 1 cup in the OEM sleeves and 2 quarts in the Air Lift bags, which is 8 times the volume. Again, these are very rough figures, but probably conservative so the difference is probably larger.

I couldn't decide if the Cardone was any different than the Dorman, so I aimed for the middle and the most popular with 600+ 5-star reviews and ordered the Dorman. I also ordered a new air line kit for the Air Lift bags so at least I'll be able to use them manually. Maybe I should order a bicycle pump to keep in the factory jack compartment in case I'm away from home and need to pump up.

I’m interested to see what that comp will do with the airlift bags.

 

[kbuskill]

The other thing to keep in mind is that the airlift bags will not be under vacuum, that is to say void of air, so to say that they are 8 times the volume is kind of irrelevant.

I believe the stock compressor will do just fine as far as filling the air lift bags. You have to remember that this is basically the same compressor used on the Trailblazer SS for the air bags that they run which is equivalent in size to our rear springs... which is why they are a direct swap into our trucks. It obviously isn't going to be as fast as if it had 1/4" lines or bigger but I believe it will be adequate for what you are looking to do.