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2004 buick rainier
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Discussion Starter #1
Ok, I walked outside this morning and the Rainier was sitting on its rear wheels. I have never seen it look like this before, and now I'm, trying to figure out what's going on. It is a 2004 with 75K miles on the clock. The compressor filled the air bags back up, and so far it's holding. I don't like the idea of starting to fix the air suspension, but I'm going to do some troubleshooting to see if the bags are the culprit.

If it is in fact the air bags, I want to convert over to coil springs. The most this vehicle ever tows is a 5x8 utility trailer. I know that there are various degrees of spring rate for the rear springs, and I would also go ahead and replace the rear shocks with Bilstein HD's.

Does anyone have a rear spring code for mid range firmness, or has anyone used Arnott aftermarket springs? Also do I just need to ask for the Bilstein's for a Envoy/Trailblazer with non-air suspension when ordering? Model #'s for the Bilsteins would be helpful.

Anyother insight would be helpful when tackling this project. I don't want the Rainier to have a crazy rake back to front. I would like it to sit level when the conversion is complete.

Thanks,
RB:confused:
 

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2002 gmc envoy_slt
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1,282 Posts
Well dont panic & start changing mechanical springs in yet....

My 2002 Envoy occasionally releases all of the air out of the system, and my compressor is far from giving up the ghost. If you query the forums, you'll find that 90% of the members here with the load leveling suspension have had it lose all of the air, pump back up, and havent had problems since. Its an anomaly.

This happens mostly during fall and spring, read: during high humidity times and/or wild temperature swings.
During the summer and winter months, it never does it.

As long as you dont hear any hissing noises during normal operation and the pump isnt running non stop, or as long as your pump doesnt sound like theres a handful of rocks being tossed around as the compressor runs, you likely just experienced the usual fluke in the system of the check-valve sticking, and you've got many more miles of happy compressoring to go :D
 

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2004 buick rainier
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Discussion Starter #3
That's good info. Thanks! This is my wife's daily driver, and she isn't too keen on monitoring the performance of her vehicle. I will drive this weekend and try to figure out if the compressor is constantly running or not. I have been impressed so far with the build quality (knock on wood), and haven't done much maintenance outside of the preventative kind. A few dollars won't hurt to keep it going.

-RB
 

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2004 gmc envoy_slt
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If you query the forums, you'll find that 90% of the members here with the load leveling suspension have had it lose all of the air, pump back up, and havent had problems since. Its an anomaly.
I guess I'm in the 10%!!! :(

My rear would pump back up, which went for almost 2 years. The compressor would run occasionally to level the Voy @ a stop light. One day the compressor died. Went with Arnott and am greatly satisfied. Search for "Arnott" or "Air Suspension" and good luck.
 

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2002 gmc envoy_slt
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69 Posts
Keep the air system... hell, see my write up today about taking the pump apart.

I did the arnott air bags few weeks ago.. super simple and they are nice.

The orig bags can leak at the top where the air line goes in, or the bottom of the bag creates dry rot cracks at the bottom where they spend most of the time folded up into itself...

use soapy water in a spray bottle to look for leaks...
 

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2002 chevy trailblazer_ltz
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Since the OP stated that the Ranier was sitting on it's rear wheels, that would lead me to believe that an air line from the pump is leaking.....if an air bag was bad, just one side would go down, right?

Can't imagaine BOTH bags went bad at the same time. Spay that soapy water mixture on all the air line connections, and the lines themselves.
 

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2002 gmc envoy_slt
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Since the OP stated that the Ranier was sitting on it's rear wheels, that would lead me to believe that an air line from the pump is leaking.....if an air bag was bad, just one side would go down, right?

Can't imagaine BOTH bags went bad at the same time. Spay that soapy water mixture on all the air line connections, and the lines themselves.
The compressor check valve sticks. It will release all air when this happens.

If it pumps up and doesnt happen again, it was likely the check valve. If it occurs every time he drives his Rainier, then its got a leak. ;)

Trust me, Ive been bickering with my rear air compressor since 2004 :D We are good friends (and sometimes enemies!) lol.
 

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2005 buick rainier
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3 Posts
Newbie here reviving the thread...

My folks have an 05 Rainier that has started having air ride issues, so I am looking for some direction/advice.

Their symptoms seem to be very erratic and don't necessarily point to a specific problem.

Sometimes, it can sit for a full day with very little/no sag and sometimes the tires will be hitting the 1/4 panels after sitting for as little as 15 minutes. The sagging is always the whole rear end, so I doubt its an individual bag with a leak. I followed the air lines and couldn't hear, feel, or see an leaks either. The problem also seems to be temperature independent.

The compressor runs like a top once the key is on; it fills the bags quickly and isn't making any abnormal sounds. One time, the compressor wouldn't come on at all, but flicking the manual compressor switch on and off in the trunk made the compressor come back to life. After that, it filled the bags as normal and hasn't been an issue since (likely a fluke?).

I'm kind of stumped on what may be wrong and don't want to tear apart their car without any idea on what the problem might be.

My dad wants to just replace the airbags with coils and found "conversion kits" online for $250-300. I'm guessing that GM made the bags so that they bolt up to the coil spring buckets on the frame and axle housing so they didn't have to manufacture different brackets for air-ride and coil spring vehicles. If this is the case, I should be able to just buy some Trailblazer springs for $80 from Rock Auto and save them $200, correct?

Thanks
 

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2004 gmc
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Many owners slap in coil springs. You can also find them on Ebay, or sometimes from members who have lifted theirs with Avalanche Z71 springs, and they might sell their takeoffs. To keep them quiet, you'll also need some rubber isolators that are discussed in the many threads about coil spring conversions.
 

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2005 buick rainier
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Thanks for the response. Any idea where I can start looking to try to fix the bags before I junk 'em though? I've done some searching on this forum and others, but it seems like most people aren't getting the menagerie of symptoms I am.

I guess the check valve would be a good place to start looking. Where is it located and what's its exact function? Keeping air from the bags from bleeding back into the compressor head? I guess the pressure switch could be bad too, seems to match up with the reoccurring problems better.
 

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2002 gmc envoy_slt
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Thanks for the response. Any idea where I can start looking to try to fix the bags before I junk 'em though? I've done some searching on this forum and others, but it seems like most people aren't getting the menagerie of symptoms I am.

I guess the check valve would be a good place to start looking. Where is it located and what's its exact function? Keeping air from the bags from bleeding back into the compressor head? I guess the pressure switch could be bad too, seems to match up with the reoccurring problems better.
I'd get under there with a spray bottle of soapy water and spray the bags, usually at the bottom where they sorta fold up into themselves.. they seem to develop dry rot cracks there, you can see them better when you jack up the rear and they extend further. I found the cracks will seal themselves from air leak when they are folded up under because of pressure, but when they extend, they are straighten out and allow air to leak.

The air lines where they connect on top you prob can't see, but you can reach up there and feel for air..

spray the lines where they connect to the compressor.

The switches that activate them, if the same as my envoy, are mounted on the frame near each rear wheel... you'll see them connected to the rear axle with a rod. since the rear drops evenly, I'd doubt its those, since there is one on each side to allow air to just one bag at a time if needed.. but anything is possible.

The switch in the rear hatch only turns on the compressor and then allows air to go to the air line for accessories, not to the bags. The compressor directs the air flow using 3 solenoids inside of the compressor itself, depending on which wheel sensor is telling it needs air, or the rear hatch switch like you did...

Those can get gunked up and need cleaning, but you may not feel up to taking the compressor apart..

The air bag system works great when its working... I chose to keep bags by getting new ones as many did here because it works so well.

The compressors are crap tho... very prone to failure.

The check valve is in the compressor.. you will have to take the compressor off... and then on the outside there is a small access cover on the side, two screws holding it on. From there you can take the check valve out and clean it.. they get gunked up pretty bad too I've found..

Just guessing, but I'm thinking your bags are leaking.. with the top connection to the lines a close 2nd, and your compressor failing a close 3rd.

* If you dad decides to go w/ springs, I was about to post a want ad to buy a compressor.. so if you could keep me in mind and send me an email I would appreciate it.

Steve
 

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2005 buick rainier
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I'd get under there with a spray bottle of soapy water and spray the bags, usually at the bottom where they sorta fold up into themselves.. they seem to develop dry rot cracks there, you can see them better when you jack up the rear and they extend further. I found the cracks will seal themselves from air leak when they are folded up under because of pressure, but when they extend, they are straighten out and allow air to leak.

The air lines where they connect on top you prob can't see, but you can reach up there and feel for air..

spray the lines where they connect to the compressor.

The switches that activate them, if the same as my envoy, are mounted on the frame near each rear wheel... you'll see them connected to the rear axle with a rod. since the rear drops evenly, I'd doubt its those, since there is one on each side to allow air to just one bag at a time if needed.. but anything is possible.

The switch in the rear hatch only turns on the compressor and then allows air to go to the air line for accessories, not to the bags. The compressor directs the air flow using 3 solenoids inside of the compressor itself, depending on which wheel sensor is telling it needs air, or the rear hatch switch like you did...

Those can get gunked up and need cleaning, but you may not feel up to taking the compressor apart..

The air bag system works great when its working... I chose to keep bags by getting new ones as many did here because it works so well.

The compressors are crap tho... very prone to failure.

The check valve is in the compressor.. you will have to take the compressor off... and then on the outside there is a small access cover on the side, two screws holding it on. From there you can take the check valve out and clean it.. they get gunked up pretty bad too I've found..

Just guessing, but I'm thinking your bags are leaking.. with the top connection to the lines a close 2nd, and your compressor failing a close 3rd.

* If you dad decides to go w/ springs, I was about to post a want ad to buy a compressor.. so if you could keep me in mind and send me an email I would appreciate it.

Steve
Thanks Steve, I wish I was in town for longer than a few days for the holidays because I'm sure I could find the problem, and its probably a pretty simple fix. I did notice some dry rotting on the bottom of the bags while I was crawling around under the car yesterday, but it didn't seem terrible and I couldn't feel any air coming out after jacking it up. I'll have to try soapy water, might not be able to feel a pin-hole like with my hand.

Maybe I'll just need to visit them for a weekend, and tear the back half of the thing apart, replace the bags, and drop the tank to figure out why the fuel gauge has stopped working too :bonk:

I'll tell my dad you might be interested in the compressor if he decides to just go to springs instead of replace the bags (if I do figure out that's the problem).
 

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2004 buick rainier
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One day I noticed that the air compressor would run much more frequently than usual and I could hear it kick in while just sitting in the garage. Shortly after noticing that, I went to start the truck up and the battery was completely dead!

After getting the battery recharged, I took it to both a small town mechanic as well as GM dealership service department and they both have told me that because the compressor ran so much, that it must have drained the battery. Neither noticed any leaks and have said that the compressor needs to be replaced before they could find out if something else was wrong too.

That doesn't seem like such a big deal except for the fact that I was told it was going to cost $1200 to replace! :eek: And that didn't even guarantee that it wasn't something else like the sensor, telling it that it wasn't lifted all the way up!

It was suggested by the service guy at the dealership that an easy (and much cheaper) "work around" would be to let the compressor lift the vehicle up and then just pull out the fuse so it wouldn't keep running. The fuse option seems to work for a little while and then the vehicle eventually loses air and lowers so I have to plug the fuse back in, let it lift up, and then pull the fuse out again.

From what I'm reading here, it seems like it should be a lot cheaper than $1200 to replace! Am I missing something?

Please help!

:thx
 

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2004 gmc
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Make some junkyard calls, or replace it with an aftermarket unit from Arnott Industries. Search for "Arnott" and enjoy reading about how other owners solved the problem for a lot less money. Or throw out the entire overcomplex system and put in coil springs with Airbag1000 bags inside the coils if you really need adjustability.
 

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2004 buick rainier
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Should I try to fix the air compression system or replace with coils?

Hi,

Everyone on here sounds like an expert -- I know nothing about cars, parts, or repairing my own vehicle, so am hoping to get some advice from the forum.

My 2004 Buick Ranier (113K miles) is having the same problems everyone else on here is talking about -- compressor running all the time and draining the battery, car "sitting down" while driving so that I'm bouncing all over the place, etc.

Mechanic said the air bags are leaking and suggested replacing those as a first step ($600), but also said that might not fix the problem and the next step would be replacing the compressor ($500).

After reading the thread on this forum, I asked him how much it'd be to bypass the air compression system and replace air bags with coils and he said that'd be $500.

Questions:
1. Do these prices sound fair?
2. Should I scrape air compressor for the cheaper coil fix?
3. If I do that, how will it impact the ride?

Any advice would be greatly appreciated :)
 

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2002 gmc envoy_slt
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that stem is where you can hook an air hose to it, and then turn the pump on with the manual switch.

You can use the air hose to air up basketballs, footballs, water mattress, etc..

Vehicles came with an air hose originally, but seems that most have been lost over the years.
 
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