Air Dump

[VinceU]

Retract the jacks air bags fill first.
Level up, airbags dump first.
No air add pessary.

[FOURWHL]

My air bags leak out in after setting for a couple of weeks, but it really doesnt take long for them to air back up once I start it up. 2-3 min tops.

I've been in a couple of spots where dumping the bags to drop the rear would help with leveling so I'll probably have freightliner add it next time its in the shop. More of a nice to have though than a must have.

Leveling is perfectly functional without the dump, you just end up a little higher on the jacks really.

[shultz01]

I was told that cycling the park brake a few times bleeds the system down and empties the suspension bags. Is this not a recommended method?

[halla]

I am not sure that would lower the air bags too, hopefully someone else can chime in

[bclemens]

We've done that, but most jacks want the engine running to make sure proper voltage is getting to the jacks..so its tricky.

I would say 98% of our users I never hear a single complaint. The 2% that complain, think they should be able to push a button and level the unit on the side of a mountain.

And for ALLLLLL the reasons to buy a nice safe truck body over a Class A, one potential drawback is that the front suspension is SPRUNG. Not air. So there is no way to lower that and sometimes the jacks do not have enough throw and you might need to use blocks to get level. Which, don't even get me started on the names I've been called for that inconvenience.

[letsgorving]

I'm sorry, but the man(bclemens) "among other great things" is a comedian
Guess he has to be sometimes....

[FOURWHL]

I've yet to run out of stroke on the jacks but for some reason cross slope (side to side) seems to throw the system into a tizzy.

And yes I often times do try and level on the side of a mountain. Parked sideways no less!

I'll be having a dump installed in the next month or so when it goes in for service. I'll share my findings then.

[FOURWHL]

Another odd note ... I end up having to drive the tires up on blocks to fool the unit into thinking its level and then it works just fine. Which means the jacks have plenty of length. Still trying to sort that one out.

[rickkey2]

I have always liked the look of the Dynamax coaches but did not realize that they did not have air dump and if I understand right, it has springs on the front and not on bags. I have a 2007 Charleston and I also prefer to use manual and not auto, when I use auto it always seems to high. On mine it says to have the engine or generator running or to be plugged into shore power to keep the batteries charged while leveling. I then put my system to on and hit the manual or auto button and it dumps the bags then the jacks will start down. When I hit retract all, the jacks must be fully retracted and the air pressure full then the bags will start to inflate. Mine has a Power Gear system and the coach is ten years old, but works as advertised.

[bclemens]

We're looking at adding a manual dump.

The front is sprung, but the bag is air and the seats are air ride. Nice compromise.

[Webefine]

So I started looking into installing an air bag dump on my DX3 today. I spent about an hour at a truck parts store with a very helpful guy that really knew his products and what I needed to do. So it seemed pretty simple, they sell a 12 volt dump valve that you install in between the air ride height adjuster and the air bag. There is a 3/8'' plastic line that you would cut and install the dump valve and wire it to 12 volt through a switch. The valve is normally open to let air to the bag but when you throw the switch it would dump air from the bag but not the whole system. When I started to think about it that meant that as long as your system had air in it the valve would have to have power to it to keep the bags dumped. This didn't sit well with me because it meant that if I were boon docking I would have to have power to the valve until the air system bled off which could be days or drain the air system myself. Then I came up with what I am going to do although it my not be for everyone. I am going to install a manual dump on each side using 2 ball valves a Tee and some compression fittings. One valve will be to stop air from going to the Bag and the second valve will come off of the Tee to dump the air. I am going to install the valves in the storage bins right behind the rear tires and route the plastic hose in and out of there. The reason I like this set up is I use my Rig in some areas that are not very level, with the manual valves I can dump one side, both sides or let a little air out or let all the air out so it gives some adjustability. I know I am giving up some convenience of just pushing a switch but I'm ok with that.

I am open for some pros and con comments.

[Kenny kustom]

I like the manual dump. Sounds like the better way.

[CSWVK]

Sounds like a simple solution for the times when you will need it. Please post pictures as you progress with the install & when you finish the install if possible. Thanks for your ideas.

[Ryan1]

What about a relay to let the dump pull power direct from the batteries? Can't imagine it has enough draw to kill them too quickly.

Then you kill power to EVERYTHING in the coach and still retain power to the valve when needed

[Webefine]

Ryan1 that would work but at this point I am convinced that the manual valves is the best set up for me. After thinking about it some more I am going to take it one step further and add another valve and tie in to the supply line feeding the height adjusting valve. With this I will not only be able to lower the rig in controled amounts but I will be able to raise the rig the same way. Raising the rear will come in handy not only for leveling up but for extra ground clearance at the tail while driving in and out of off road riding areas.

[Ryan1]

I haven't tried on a coach, but the "ride height" we use on lowered trucks with bags uses a sensor to set the height. So if you used an electric valve to raise/lower would the system take over and automatically dump/add air depending on the situation?

[FOURWHL]

Would the HCV operate when the vehicle is off? I'd think youdo only need to power the solenoid when the truck was running.

In other news I struck out at the dealer today. Apparently an oil change is all they have time for. I think I'might just going to tackle this myself

What solenoid valve were you looking at Ryan1?

Brian any chance you can get specs or a part number for the ones you guys are looking at putting in from the factory?

[Webefine]

The height control valve is 100% air no electric so if there is air in the system it is going to try and put air in the bags even if the rig is turned off. For me the manual valves are going to work best because of how I use my rig and the places I take it. Electric solenoid valves will work great for some who just uses campgrounds and rv parks.

[Ryan1]

SMC valves.

For folks that want an electric option you could put a valve in line that opens with a switch or tied to ignition (fail safe to not drive off with empty bags) and then a dump valve on a Tee between the bags. Then you kill power to the inline valve and it closes...then you hit the button to dump the rear. If you use a momentary rocker you could control the height anywhere between empty and full.

If you tied it to ignition then all you'd have to do is turn off the key and dump air. Then when you turn the key to on it'd air right back up.

No draw on the battery while not in use either.

[Webefine]

Very good thinking! 👍