Rear air suspension down since snow GMC

rear air suspension seems to be down.

My car has 91000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi – your "low suspension" may be a leaky air bag, pressure check valve, bad air pressure sensor, or blown fuse or relay for the air compressor. Weather changes to cold weather causes air contracts (actually shrinks somewhat), but your air suspension system should be compensating for this. I would recommend an air suspension system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Air contains a lot of evaporated water which condenses out of the air when it is compressed. It is this moisture that freezes. Additionally, you can run airbrake anti-freeze through the air pipes to further winter-proof your air suspension.
If your air suspension fails, you can likely drive to your local Advance Auto Parts, mechanic, or home, but you shouldn`t continue to daily drive with the failure. Failed air suspension parts cause negative handling characteristics and it beats up the rest of your vehicle.
The air suspension system cannot function without the compressor. If the compressor does not come on at all, that may be a sign that it was overworked and has burned out or it could be as simple as a fuse or relay problem. Of course, referencing a proper wiring diagram is where the analysis should always begin.
One of the most noticeable symptoms of a potential problem with the compressor is abnormal noises during operation. If you hear any sort of abnormal sounds, such as excessively loud clicking, whining, or grinding, then that may be a sign of a problem with the compressor`s motor or fan.
Can air suspension be used in the winter? Most certainly yes! While winter does provide some unique challenges to driving, some simple maintenance on your air system can make cold climate motoring a non-event.
It is fairly well known that your suspension changes as it heats up or cools down. It can be slow and boggy in the cold or harsh and fast in the heat. Many people will also know that oils get thinner when they are warmer so this is assumed to be the main cause.
On average, an air suspension part should be replaced between 6 to 10 years or between 90.000 to 160.000 kilometers because the rubber will have dried out. Off-road use also influences how often the replacement should be done. Over this time, the rubber bladder dries out, and cracks appear around the bottom piston.
Your suspension may suffer malfunctions from rust or moisture damage from the inside, or an air fitting failure of the air tubing connecting to the air system. Leaks in air springs are also common and could lead to compressor burn out.
The good news is that most air bag suspension systems are pretty self-sufficient and require little maintenance. With that being said, there are a few things you will want to check for, and depending on the climate, a few preventative measures can be taken to keep your system in check.
“Stiff” shocks are caused by cold oil, a common problem in the winter season. According to DIYAutoService, “a drastic decrease in temperature causes your shock absorbers to restrict the movement of fluid through the metering holes as the oil inside gets thicker and denser.”
Over time, suspension springs will begin to sag a bit, and they can lose some of their “springiness”. However, outright failure is very rare, and most drivers will find that their springs last for the life of the vehicle.
The simple answer is YES! Like most things, you won`t have any problems if you take your time on a good install. Your air suspension is going to be as reliable as you make it.
Since air suspensions run off of air, it is relatively typical for air leaks to occur when there`s an issue. The various parts of the suspension offer different avenues for air to escape, which include the rubber seals that are susceptible to holes and punctures.
Damage to Shocks and Struts

In addition to obvious tire damage like a blowout, repeatedly running over potholes can cause damage to many other parts of your vehicle as well, including suspension system components like shocks and struts.

Prior to jacking or lifting a vehicle with air suspension, you must turn off the suspension switch. The switch is generally located in the trunk or on the right side of the passenger foot well.
Typically, a high-quality air spring should be replaced every six to ten years. Outside conditions including climate, road conditions, and constant abrasion of dirt and road debris also influence the functioning and life span of these air suspension components.
Thaw out frozen air lines and valves by placing the vehicle in a warmed building. This is the only method for thawing that will not cause damage to the air system or its components.
Your suspension may suffer malfunctions from rust or moisture damage from the inside, or an air fitting failure of the air tubing connecting to the air system. Leaks in air springs are also common and could lead to compressor burn out.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

’08 Nav Needing Air Suspension Help
ANSWER : It is possible that you could have a restriction in the line that goes from the compressor to the rear air spring. This resriction would prevent the air from reaching the air spring. I would recommend dis connecting the line at the compressor and at the air bag and shooting compressed air through the line to make sure it is not restricted. If something comes out of the line, you should be able to reconnect the lines and the air suspension system should work properly again.

My heater is blowing air through the driver side air vents but is blowing cold air through the passenger side and rear console ven
ANSWER : Hi there:

Climate controlled vehicles have multiple electrical relays that open and close vents to maintain the desired temperature. In some instances, these relays can wear out overtime. However, it’s also common for debris to clog up vents (especially side vents) which may restrict the flow of cool air. The best way to determine why your AC is not working efficiently, it might be best to have a professional mechanic complete a AC inspection; so they can pinpoint the source of your issues and recommend the right repairs.

Air compressors and air suspension fail
ANSWER : This is a common fault that is found with vehicles that have air suspension. Though the compressors were most likely bad the first time, there is another problem causing them to fail. The most common would be a leak in the system or a failed air strut.

When the strut fails or a leak is present, it can cause the air compressors to never shut off as they try to compensate for the leak which causes them to fail prematurely. A qualified technician, such as one from YourMechanic, will be able to inspect your suspension system and make a proper diagnosis on the issue.

Rear air suspension down since snow GMC
ANSWER : Hi – your "low suspension" may be a leaky air bag, pressure check valve, bad air pressure sensor, or blown fuse or relay for the air compressor. Weather changes to cold weather causes air contracts (actually shrinks somewhat), but your air suspension system should be compensating for this. I would recommend an air suspension system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

Loud banging from rear suspension of Ford e350 cutaway van single wheel rear not dually.
ANSWER : Look at the suspension on the rear of the van and see if there is anything that looks broken. If not, then the bushings on the shackles on the leaf springs could be damaged causing the leaf springs to shift when going over bumps causing them to bind up. If not, then the leaf springs could be cracked causing the spring to be weak and making the spring bumper hit the frame. If you need further assistance with your suspension making a banging noise on the rear, then seek out a professional, such as one from Your Mechanic, to help you.

Hot air mixed with cold blows from air conditioning
ANSWER : Hey there. You will most likely have to have a mechanic bypass the heater coolant lines to have this resolved. Your A/C may not be controlling the air flow inside the evaporator correctly out of the vents and may be the blend door actuator stuck in the heat position. Have the AC system diagnosed first before bypassing the heater.

How much would it cost to convert a 98′ range rover from air suspension to spring suspension?
ANSWER : The cost of conversion varies depending in part on where you purchase the conversion kit from. I suggest finding a kit with all the components needed rather than piecing it together. Cost will also vary depending on the quality of the components. To get an idea of the cost to install, YourMechanic can provide you with a quote for a suspension springs replacement. You will need to enter information about your vehicle and your location. You may need to call our service line at 1-800-701-6230 to clarify the job you want us to do and to determine the final cost of labor. Many kits will state the time needed for installation.

Cold mist/smoke like air comes out of the air vents when cold air is on.
ANSWER : If you are using regular outside air a/c instead of recirculated air you may be getting a large amount of outside air humidity and can cause a mist to come out of the a/c vents. You should make sure the a/c evaporator drain is cleared and drains freely or the water in the a/c cannot drain fast enough and the blower will pick up the water and blow it out the vents.