Air suspension issues (or "#%$@!" again!)

[mdoyle]

I've got a 2003 H2, adventure pkg with air suspension.

Here's the problem that defies logic, about 75% of the time after the truck is parked for a few minutes, the air suspension will be totally lowered. When I start it, it returns to ride height.

The first reaction is there is a leak, but that doesn't explain why it isn't consistantly flat. It also seems the suspension is constantly changing, I hear it cycling at stop lights on flat ground sometimes.

I've gotten no warning lights and I always wait a minute or two for it to inflate before driving but the problem seems to be worsening and lately has affected ride height on the highway.

After searching this site I didn't see any similar problems and I'd rather fix it myself. My first guesses are either of the position sensors or a relief valve.

Has anyone had a similar problem? My concern is the dealer might be inclined to replace more than necessary.

[timgco]

This has been talked about a lot here! The 03's had the most issues with the air susp. IMO. I lost two air bags and had a few dealer trips due to the air susp. on that truck. Because of this happening, I was also stranded on a trail.. AFter that, I opt. for no more air susp. Solid steel springs make me feel better about the susp. and saftey on trails. Others have zero issues.

So, yes your compressor will turm on and off while driving and sitting at stoplights. That part is normal.

When you come out to your truck in the morning and it's sitting low, that's not good. Do you have anything screwed into your fitting in the back of the truck (where you screw your hose into) If so, unplug it, that's your issue.

You can check your ride height arms in your rear wheel wells to see if they are damaged.

Otherwise off to the dealer you go.

If you're really sick of this issue, you can swap out the air bags for springs. It may be a cheaper route if you are out of warranty.

[DRTYFN]

After having experienced just about every kind of air suspension(AS) problem possible I can tell you that the two main areas of concern are the AS sensors and the air bags. Back in '03 when I had most of these problems finding & fixing them was a major endeavor for the techs as the system was still new to them. Now they know exactly what to look for.

[Big Z]

No Air, No Problems!

[timgco]

Originally Posted by Big Z

No Air, No Problems!

I agree. Try GasEx for this.

[working Hummer]

I have air ride also on an '03 and it is always clicking on and off at a stop light or drive thru and that is normal. As we all know when the truck is not running there is no pump, so my uneducated guess it has to be a leak somewhere in the pillows or line, because when the truck is running the pump keeps them inflated so it has to be a SMALL leak, leaking when the truck is off. Check the most obvious first. Thank you and good night sir!

[mdoyle]

Guys thanks for the replies so far. Sometimes the suspension will stay up fine for 24 hours or more, and we have a steep driveway so it's under pressure from weight transfer.

I've inspected the sensor arms and they are undamaged and I searched this site but the search feature misses post sometimes.

I'll tear into the system this weekend, my suspicion is a solenoid controlled relief valve is sticking open sometimes, but I don't have a shop manual for the system so I'm flying blind at this point.

I'm out of warranty and don't want the dealer to just drop in a new system for 2K+ as an easy fix (for him) if it's just a valve. I've got a full shop and experience, hell if I have to I'll make a new part on my lathe.

[CO Hummer]

Originally Posted by timgco

Others have zero issues.

That would be me. 2003 bought in Feb '03 and have never had an air problem.

However, I have noticed that my air levels out and different heights. Appears that it's varies by about 1" or so. I know this because sometimes my rig with new 37s hits the top of my garage door, sometimes it doesn't.

[H2 Bill]

I had the same problem. It turned out to be a leaking bag. What was weird is that it was intermitant. Some days it would stay up and others it would sag a little and sometimes it would go all the way down. It took two dealers to figure it out.....

[HUMTECH]

If this is an early model H-2 with A single stage compressor there is a programming update to address your concern, talk to your dealer tech and he should know about it. Likely the service consultant or service manager will not have the info.

[mdoyle]

I thought I'd post a follow-up here to complete the archive. I took it by the dealer and they said it's the airbags so I feel like I've dodged a bullet of sorts since the compressor is okay.

The bags were $158.00 each (thinking I saw a post here mentioning $90 each?) plus labor and will be installed this Friday.

I'd planned to look at the system this weekend, but a very enjoyable soccer tournament kept me busy. Yesterday evening I climbed under to have a look and both air bags are dry rotted and cracked badly, it's a wonder they hold air at all.

I wonder if I got a bad original set, or if some preventative protectant should be applied when the new ones are installed? It's lame that these would go out due to deteriotation at 70K miles.

[PARAGON]

Originally Posted by HUMTECH

If this is an early model H-2 with A single stage compressor there is a programming update to address your concern, talk to your dealer tech and he should know about it. Likely the service consultant or service manager will not have the info.

x2

mine is a July '02 version and I got the update because I was having an abnormal about of cycling.

[PARAGON]

Originally Posted by mdoyle

I thought I'd post a follow-up here to complete the archive. I took it by the dealer and they said it's the airbags so I feel like I've dodged a bullet of sorts since the compressor is okay.

The bags were $158.00 each (thinking I saw a post here mentioning $90 each?) plus labor and will be installed this Friday.

I'd planned to look at the system this weekend, but a very enjoyable soccer tournament kept me busy. Yesterday evening I climbed under to have a look and both air bags are dry rotted and cracked badly, it's a wonder they hold air at all.

I wonder if I got a bad original set, or if some preventative protectant should be applied when the new ones are installed? It's lame that these would go out due to deteriotation at 70K miles.

there's really no reason they should have deteriorated to that degree so quickly. They are not exposed to sunlight. The only other thing would be if certain chemicals made contact with them, maybe at a detail shop or something.

[CO Hummer]

Originally Posted by PARAGON

x2

mine is a July '02 version and I got the update because I was having an abnormal about of cycling.

So, what is an abnormal amount? Most of the time, my truck will audibly release air when I shut if off. It then pumps itself back up a bit after I start it up. I'm assuming that is normal. Maybe not!

[Agriv8r]

[PARAGON]

Originally Posted by CO Hummer

So, what is an abnormal amount? Most of the time, my truck will audibly release air when I shut if off. It then pumps itself back up a bit after I start it up. I'm assuming that is normal. Maybe not!

abnormal is it was either pumping or releasing..... it was a huffer. never held it's breath.

[Hum2]

Had numerous Air suspension sagging/cycling issues, no leaks though.

Final fix was to have it replaced with the dual stage compressor that came out with the 04's. It is also the standard replacement for the 03' as the single stage one was discontinued. No problems in the last 3 years with the dual stage.

Ric

[mblovsks]

I have an 07 and after 5.5 years, I am looking at the second time now that I've walked out to a low back end. Any ideas?

Thanks.

[wasp1971]

I swapped to springs so no more air bag issues. It's pretty easy to do too. I don't recommend the bilstein shocks. I got them and it feels like I have sponges on all four corners.