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Discussion Starter #1
Took delivery of my new 3500 DRW a few weeks ago and today my airbag system threw a fault saying “Air suspension needs immediate repair” or something like that. Naturally I’m 600 miles from home and have to tow my 5th wheel back on Sunday. I stopped at a dealership in Denver and they couldn’t figure it out other than it’s something to do with the compressor. The bags themselves are ok. Guess it’ll have to wait until I get it back home.
 

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Couldn't you just inflate the air springs to the pressure of your liking, after temporarily putting Schrader valves or other suitable couplings on the hose ends, then worry about the problem when you get home?
 

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On 3500’s I think it’s just a supplemental system over your springs to keep it from sagging under really heavy loads. Unless your 5th is really heavy you should be fine for drive home. I wouldn’t worry unless you are sitting on the bump stops. If you are move weight to back of trailer and that might help.
 

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The springs with the air option seem to be more of axle locating devices than load carrying. Not that I've tried deflating/disabling the air springs, but it probably wouldn't take all that much load to end up on the bump stops.
 

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The springs with the air option seem to be more of axle locating devices than load carrying. Not that I've tried deflating/disabling the air springs, but it probably wouldn't take all that much load to end up on the bump stops.
You could be right, not sure what those springs can take if bags had no air at all.
Although his bags may still hold air.

I would be bummed though and would want to fix before towing home. I’m surprised the dealer he saw basically blew him off. Aren’t they supposed to be there to fix things?? Lol it’s not like he brought them a Maserati with a problem.
So many garbage dealers out there.

I’d call FCA and report how a new truck is broken away from home and that dealer there blew him off. That’s really bad. If they can’t diagnose and fix a simple system like that they have no business servicing or selling anything.
 

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Discussion Starter #7
It was close to the end of the day and the dealer did offer to keep it to look at it tomorrow, but they don’t do loaner vehicles and we were 2 hours from the campground. He did say that the bags were holding pressure and that it wouldn’t hurt anything to tow home with it, just that it won’t auto-level.
 

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It was close to the end of the day and the dealer did offer to keep it to look at it tomorrow, but they don’t do loaner vehicles and we were 2 hours from the campground. He did say that the bags were holding pressure and that it wouldn’t hurt anything to tow home with it, just that it won’t auto-level.
I think you're the first person I've seen anything on here with an air suspension fault.

But, yes, so long as the bags are holding pressure, drive it home.
 

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It was close to the end of the day and the dealer did offer to keep it to look at it tomorrow, but they don’t do loaner vehicles and we were 2 hours from the campground. He did say that the bags were holding pressure and that it wouldn’t hurt anything to tow home with it, just that it won’t auto-level.
That makes a bit more sense.
Good luck with it!
 

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It was close to the end of the day and the dealer did offer to keep it to look at it tomorrow, but they don’t do loaner vehicles and we were 2 hours from the campground. He did say that the bags were holding pressure and that it wouldn’t hurt anything to tow home with it, just that it won’t auto-level.
I would probably disconnect one end and secure the links before driving, so there's no chance for the links to induce any pressure loss.
But if you do lose pressure, it wouldn't be a big deal to put more air into it. A truck shop should have the necessary fittings, and knowledge.
 

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I would probably disconnect one end and secure the links before driving, so there's no chance for the links to induce any pressure loss.
But if you do lose pressure, it wouldn't be a big deal to put more air into it. A truck shop should have the necessary fittings, and knowledge.
Thing about doing something like that is warranty concerns, they sure could throw the blame on the owner for messing with the system like that.
 

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I'd like to know where that rumor started. An enclosed system wouldn't make sense in so many ways.
Pretty sure I read that on here somewhere a few years back as well.
 

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Pretty sure I read that on here somewhere a few years back as well.
It'd be an interesting challenge to make an enclosed system. There would probably need to be compressors and/or vacuum pumps working with additional storage tanks to compensate for temperature and altitude changes, for example.
Plus a really large and/or highly pressurized main tank to draw from as whatever pressure is in the system to start with would have to last at least a year or two (without any noticeable leaks) before needing to be topped off again...at the dealer.

I would imagine that if NASA needs compressed air, or whatever, it has something along those lines as the space stuff can't rely on a regular compressor and storage tank.
 

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It'd be an interesting challenge to make an enclosed system. There would probably need to be compressors and/or vacuum pumps working with additional storage tanks to compensate for temperature and altitude changes, for example.
Plus a really large and/or highly pressurized main tank to draw from as whatever pressure is in the system to start with would have to last at least a year or two (without any noticeable leaks) before needing to be topped off again...at the dealer.

I would imagine that if NASA needs compressed air, or whatever, it has something along those lines as the space stuff can't rely on a regular compressor and storage tank.
I wish I had the repair manual for these things, so I could verify exactly how it's set up. Someone on here did their own self leveling repair and they said they had to charge it with nitrogen. There is a connector on the air tank that is like a charge valve on the a/c, and supposedly this is where you fill it. It was claimed that the system wouldn't work without the nitrogen charge, wouldn't fill on it's own from completely empty. There is supposedly a fill kit sold by mopar.
 

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Look at this diagram pic of the 2500 rear air suspension:


The compressor is in the middle, between the storage tank and the suspension bags, so, conceivably, the pump could be pumping the bags up as well as down, so it could be nitrogen filled, or at least a closed system. This arrangement is the same on both 2500 and 3500.

I can tell you that I've never heard any air blow down from mine when setting the suspension to the lower level from normal ride height.
 

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Look at this diagram pic of the 2500 rear air suspension:


The compressor is in the middle, between the storage tank and the suspension bags, so, conceivably, the pump could be pumping the bags up as well as down, so it could be nitrogen filled, or at least a closed system. This arrangement is the same on both 2500 and 3500.

I can tell you that I've never heard any air blow down from mine when setting the suspension to the lower level from normal ride height.
The air blow down, is that not because on a transport truck the air compressor is always driven so the unloading valve exhausts to atmosphere? Also air blow down could be an air drier on those systems.
Now saying that, when I have put my 3500 into transport mode with truck off and key to RUN to try and load motorbikes, I heard air relief without hearing anything like a compressor running.
The way that system is laid out in that diagram, it wouldn't be hard for simple valving to change the direction of the compressor, pulls from tank to lift bags, pulls from bags and sends to tank to lower bags.
 

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On a 18 wheeler with air suspension, the compressor pumps air only to the storage tank, the tank supplies air to the height control valves, those valves have the blow down tube that vents air from the bags to atmosphere when necessary. And, they have a air drier, and it is constantly blowing off any accumulated moisture, which you hear as it happens.

On the RAM, the height valves are electronic, the air doesn't pass through them, they only tell the pump when to operate, and whether it needs to go up or down.
 

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