2021 Spirit 26T Class C Rear Airbag Dump When Leveling

[Tom8905]

I haven’t had experience with airbag suspension so this may sound stupid. My airbags dump all the air when I use my hydraulic levelers. So I only have airbags until the first campsite which wouldn’t be a problem on a class a with air brakes and an onboard compressor. Is this normal? Am I supposed to be hauling around a compressor? They seem pretty useless if that’s the case. A 26t has very, very limited storage.

 

[Waterbug]

I'm not familiar with your RV, but it sounds like your air bag suspension is an after market addition, maybe by a previous owner. Every vehicle that I have owned with factory air bag suspension has had an onbourd compressor. Most automatically adjust airbag inflation with leveling.

 

[Tom8905]

I'm not familiar with your RV, but it sounds like your air bag suspension is an after market addition, maybe by a previous owner. Every vehicle that I have owned with factory air bag suspension has had an onbourd compressor. Most automatically adjust airbag inflation with leveling.

Maybe it’s not actually “airbag suspension” but goes by another term. I bought it new so I wouldn’t think aftermarket. I have two valve stem type gizmos mounted in the left rear wheel well. I take the cap off and air them up to about 50 psi causing the rear of my class c to lift. It’s kind of like the “air ride” seats in the old semis I used to drive. It does seem to ride better until that first campsite when the air is dumped but I seldom use it because I don’t travel with an air compressor. It would be great with onboard air system.

 

[Waterbug]

That just doesn't sound like something Winnebago would install at their factory. Maybe a dealer added item or something that has NEVER performed as expected.

 

[tderonne]

No mention of them dumping when you use the levelers in the owners manual I read. Just says to adjust the pressure. Nothing about every trip or anything like that. It has done that since new? Do they hold pressure until the levelers are used?

 

[Morich]

It looks like this is a different item than airbags and called " Airspring"!
Looks like standard OEM installed, not as an option, etc.

I might go for calling Winnebago to ask about how they are expected to work? Does not seem correct to need aired with a compressor each time. But they DO show the two points mentioned to fill. With two different fill valves and tubing, it doesn't seem correct that a single line failure would dump both, if it was a case of a jack hitting something to dump one?
Perhaps a search for any info on Airspring operation?
Odd duck to me!

 

[creativepart]

Generally, the rear airbags on a Class C like your Spirit are simply helper springs to adjust for load conditions, not an Air ride suspension.

I don’t think it’s normal for the air bags to dump when leveling on a Class C. It is normal on a diesel Class A.

When I owned a Class C with rear airbags the airbags did lose pressure over time and I did need to adjust the pressure fairly regularly but not every time I leveled the RV.

 

[Tom8905]

I think you are correct Creative. My airbags are to adjust for weight not ride. I was just reviewing my Owners Information and in the section about the HWH 725 leveling system one of the first steps it does is dumping the air from the suspension. Looks like some models also have a manual air dump button on the control panel. Maybe it was all Winnebago could get during early COVID mfg. but it definitely seems useless on a Class C without onboard air. Thanks to all!

 

[klook]

IF it dumps air, it must also pump up. I have the air bags for leveling on my 04 Minnie Winnie. It was factory installed. I would run the engine and move it and park again and see if it dumps again....Can't dump unless it is filled. And how did it get filled the first time?

 

[Tom8905]

It only dumps air when I fill it with my compressor before leaving for a trip. After the first leveling, it doesn’t dump again until I fill it again which I have pretty much stopped doing.

 

[klook]

That is interesting.

 

[klook]

Have you looked for the dump valve location? Maybe disconnect it....

 

[Waterbug]

This is completely off topic, but while in high school, I had a 1958 Pontiac with factory airbags suspension. It had on onboard compressor attached to the power steering pump. When parked, there was a manual control under the dash that could raise and lower the vehicle by front or rear zones. Parked it one day raised like a 4X4, next day like a low rider, next day raked and the next nose up. The compressor and supporting tank also supplied my after marker semi air horn, which just got me into trouble.

 

[RVSpirit26T]

I haven’t had experience with airbag suspension so this may sound stupid. My airbags dump all the air when I use my hydraulic levelers. So I only have airbags until the first campsite which wouldn’t be a problem on a class a with air brakes and an onboard compressor. Is this normal? Am I supposed to be hauling around a compressor? They seem pretty useless if that’s the case. A 26t has very, very limited storage.

I have a 2023 26T with the same OEM Firestone air bags, they are completely separate for the HWH leveling. Each air bag has it's own air line with a Schrader valve stem at the rear wheel. The air bags contain extremely small amount of air by volume, even checking the pressure will lower it by 3psi. It's not uncommon for me to add air on weekly basis, I carry a small hand held compressor to maintain 60psi. I would suggest when you are lifting the RV to level, it is moving a loose fitting allowing air to escape.

 

[Morich]

I think the lifting of the body by the leveling jacks while leaving the rear axle to settle lower is the real problem. The above post suggests the correct idea to me. As the axle and body move apart, there is a connection which moves enough to let the air escape.
This might also point to an improvement on RV which need air added often?
Maybe a bit of Locktight on the connection, making sure it does get on any air valve involved!

Since left and right appear to be totally separate lines and air springs. I might first want to verify that BOTH go flat and then look at doing a soap solution at the connections along the line on any that appear to have leaked when using the jacks.
OR
doing a bit of tightening on both sides to see if that cures the problem might be as easy as searching for a loose one?
I might guess that there would only be one connection at the bags and one at the valves on each side of the setup.

 

[DaPreacherMan]

our 87 chieftain has a air spring system in it. In our manuals, i read that before you start the engine, let the system come on and electronically adjust for a few minutes.

when i put the key into accessory mode, the red compressor light comes on and i can hear the compressor in the back running. while its running, you can see/feel/hear the chassis moving up/down. Once the compressor stops and the light goes out, it ready to start.

 

[Morich]

Different systems on different RV. This is a system which has air valves located near a rear wheel that have to be aired with a stand alone compressor.
You have a much higher level system which adds air on each start.
This one allows the user to adjust the chassis to fit different loads instead of doing it automatically .
Something like what we might call manual versus auto?
One of those small points I had never noted before. One of the things I have learned about RV is that they may all be different!

 

[RV_Lee]

Class A diesels also use the same HWH levelling and that is what your manual is talking about when it mentions dumping air. I have the same rear air springs in mine and the HWH 725 system. They are totally separate and have nothing to do with each other. You have a leak.

Also, 50 and 60 psi in them gives a very rough ride. I've been running them at 35psi, much smoother.

 

[RayIN]

That just doesn't sound like something Winnebago would install at their factory. Maybe a dealer added item or something that has NEVER performed as expected.

I agree. The sales brochure states the 26T has spring suspension and hyd. leveling jacks, no mention of optional air suspension. https://www.winnebago.com/Files/Images/Winnebago/brochures/2021/2021 Spirit Digital.X.pdf
Tom, I would stop deflating the rear air assist bags. Weight should never be removed from the rear wheels anyway unless the front wheels are securely blocked to prevent MH movement.

 

[tderonne]

Already established they were installed by Winnebago, as mentioned in the brochure: "Rear auxiliary springs (26T, 31H, 31K)"