Air Suspension?

[MRUSA14]

Originally Posted by TWINCAMSAM

Okay-you have my attention. I’m not sure I completely understand the “air” system. I have just figured out that there are two separate aspects of the air system; the air brakes and the suspension. Is that correct? Now is there two compressors or just one? Short of going to the overbooked Freightliner school, is there any way to learn. About these systems? When you put down the jacks does it dump the suspension?

One compressor that is engine driven. Some air leveling systems have an additional compressor, but that is not where your problem is likely to be. Without a good compressor you would not reach ride height or be able to release your brakes. Your problem seems to be happening after your engine (and compressor) are turned off.

I would call Freightliner or Newmar customer service and they can give you some ideas of where to look, but you can start by listening carefully for an air leak somewhere just after shutdown.

[olcarguy]

Sounds to me from what you describe that all 4 wheels are going down at the same time. That makes me think that the dump valve that controls the bags is either leaking or is being activated when the ignition is turned off or the parking brake is activated. See what happens if you only turn off the ignition switch, that might narrow it down some. best I can come up with. Good luck...by the way, my air bags stayed up all winter with no air in the tanks. didn't go down at all.

[FIRE UP]

Originally Posted by TWINCAMSAM

Okay-you have my attention. I’m not sure I completely understand the “air” system. I have just figured out that there are two separate aspects of the air system; the air brakes and the suspension. Is that correct? Now is there two compressors or just one? Short of going to the overbooked Freightliner school, is there any way to learn. About these systems? When you put down the jacks does it dump the suspension?

Twincam,
We need just a tad more info on what leveling system you have. If you have an HWH leveling system, you may or may not have a versital system that lets you manually dump the air or, it will dump automatically when using the Auto level function. But, that's only if you have an Auto leveling system. Now, you asked about if there were TWO COMPRESSORS, one for each system, leveling and suspension. And the answer you were given is ONE compressor, that handles everything.

There are control valves, diverter valves, protection valves, and a whole lot more involved in air systems. Learning the intricate characteristics of an air system is not for the meak. It's also not all that hard. One just has to be able to desipher what all the components do in the systems and, at what time. But, let me ask you this.

If you park your coach in a very secluded, QUIET ENVIRONMENT, like a deserted parking lot, at night, or in any way, a very quiet setting, then shut down the engine and set the parking brake, then get out and very carefully, LISTEN for any air leaking, ANYWHERE under the coach, do you hear anything? Again, this must be done where the atmosphere is dead silent. And if you wear hearing aids, turn them all the way UP for this test. Do not try and put your tire covers on, do not try and level the coach, don't do ANYTHING but, get out and listen.
Scott

[TWINCAMSAM]

Yes I have HWH leveling system. Yesterday I aired up then shut the engine down. Air brake is set but levelers are not down. The coach didn’t change for 5 hours. Then I checked and it was down. Yes it does have auto-level. During the first 15 mins after the engine shut down I was laying beneath the front end to midway way and it was quite as tomb. It takes less than 5 mins to air up to 100 PSI. I drove it today to the glass shop for a redo of a shotty windshield install.