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Demco SBS Coach Air Kit for Air Force One Supplemental Braking System

Demco SBS Coach Air Kit for Air Force One Supplemental Braking System

Item # SM99627
Our Price: $372.19
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Half system replaces the necessary coach installation components for Demco SBS Air Force One supplemental braking system (9599007 and 9599019) for motor homes with air brakes. 1-800-940-8924 to order Demco accessories and parts part number SM99627 or order online at Free expert support on all Demco products. Great prices and Fastest Shipping for Demco SBS Coach Air Kit for Air Force One Supplemental Braking System. Accessories and Parts reviews from real customers.
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Demco Accessories and Parts - SM99627

  • Tow Bar Braking Systems
  • Second Vehicle Kit
  • Demco

Half system replaces the necessary coach installation components for Demco SBS Air Force One supplemental braking system (9599007 and 9599019) for motor homes with air brakes.


  • Replaces installation components for Demco SBS Air Force One supplemental braking system
  • Fits all Air Force One supplemental braking systems (9599007 and 9599019) for motor homes with air brakes
  • Half kit includes components for RV-side only
    • Vehicle-side kit (SM99209) sold separately


  • All Demco Air Force One supplmenetal braking systems: 9599007 and 9599019

6231 Demco SBS Replacement Coach Installation Kit for Air Force One Supplemental Proportional Braking System

Replaces Demco SBS SM99627

Video of Demco SBS Coach Air Kit for Air Force One Supplemental Braking System

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Demco SBS Air Force One Coach Air Kit Installation - 2015 Tiffin Phaeton Motorhome

Hi there RV owners. Today in our 2015 Tiffin Phaeton, we're going to be taking a look at and showing you how to install. Demco Air Force One, second motor home kit. A second motor home kit is great, if you we're already flat towing a vehicle, but you upgraded and purchased yourself a new motor home, gotten rid of your old one, and you're ready to flat tow your vehicle with your new motor home. With your new motor home, if you have an Air Force One system, there are some components that are on the motor home side. Now, maybe you tried to reuse those from your old one or you just sold it and you don't have those anymore.

You can purchase this kit here and it's going to come with everything you need for your motor home side, so you can get that motor home, fully equipped to plug right into your vehicle that already has Demco Air Force One. On our motor home side, we have to mount up a couple of components. The first thing we need to mount up, and this is the main thing, is our tank here. And this is where all of our hoses are going to connect. You can see here, we've got our hoses attached to it, and you can really put this wherever you want to put it.

I do recommend putting it probably somewhere near the rear axle towards the back of the vehicle rather than towards the front half, just to minimize the length of hoses that you're going to need to run. We've mounted ours on a cross beam right here, just in front of our rear axle. And we just drilled straight through this cross beam, and then the tank here comes pre mounted onto the bracket. So we just ran some bolts down through the bracket and then just clamped it right on with some nuts. We did have to change the hardware out as this beam was a little too long.

So the bolts that come in your kit weren't quite long enough to go straight through it. But if you we're a mounting this like onto your frame or inside of any of your rear storage compartments, like your battery compartment, if you've got one in the back, that's a great place for it, cause the battery compartments often secluded in its own compartment. It's easy to get to, to mount it up, and it usually the battery compartment is not fully enclosed. So you can easily route your hoses in and out of it without having to drill any holes into it. Once you figure out where you're going to put your container then we need to start hooking everything up.

There's three connections that go to your tank. We're going to have one here, and then there's two on the opposite side. We're going to start with the side that has a single connection. This is the input side, the supply that goes to our tank. So this is supply air that's what's going to fill up our reservoir tank here. We're using the quarter inch airline that comes in our kit. We just poke it in and then we'll cut it to length. And this connects into a T that we installed onto the supply airline, now to determine if you can determine which line is your supply airline, you first need to drain the air out of your RV's system. To drain the air out, the easiest way to do that is while the vehicle's not running, just key off, just pump the brakes on it, and every time you pump the brakes, it's going to shoot out air. And eventually when you're going to pump out all the air and there's going to be almost no pressure left. Once you've depressurized it, we're going to be safe to remove the line here. To remove it, these are all quick connects on here. So you just push in on the collar here and then you can just pull it out. We then, after we pull that out, have an assistant start the motor home. The compressor will kick on and it's going to try to repressurize your air system. So if you have air coming out of here while it's just running, you know that, Hey, this is our supply line. It's going to be a very thick line like this, see how thick this is. and you're going to get a T, that's the correct size to slide into that. This is a quick connect, so we just pull this out and we verify that we have air coming out of it when it runs, and then we cut the line, slide our T on one end, slide the other end of our hose back in, and then we make our connection to our tank here with this quarter inch line. Next we need to make our metered air connection. This one, we also need to test to figure out which one is our metered air. The metered air will only have air coming out of it when the brake is being depressed. So to check this one, we've got to have all this back together. We'll then disconnect the wire we suspect to be our metered air, and then we'll start the vehicle. No air should come out of it while it's running. You'll have to let it idle for a minute, maybe even pressure put on the gas to increase the idle to air the system up faster, and then while this hose is disconnected have an assistant press the brakes and you should feel air coming out of it. If you do, you know, you've got the right line. We're going to basically do the same thing we did with the other T. We're going to cut it, we're going to slide our T in between the line and plug our ends back in, and then we're going to plug in a quarter inch line into it, and this routes back to our tank and it plugs in right here into the tank. So this is the static 90 degree fitting here. The last one here is going to be a swivel fitting. And then we'll wrap this line all the way to the back of the motor home. I just followed down the frame. You can see our line coming out way here in the back, and this is our connection that is going to tie the vehicle side of our Air Force One to the motor home side. This is our quick connect board at the back where we make those connections together. And then this line here is just runs in the back and it plugs into the fitting that we need to mount here at the back, and this fitting just mounts right into the panel. We just use self-tapping screws to run it in there. You could also drill holes and use nut and bolt, whichever one works best for your particular motor home. We just need to make sure it's solid. This has a swivel end on it as well, and it's a quick connect, just like all of our other fittings. So we're just gonna poke these in and here I'll show you kind of how this whole thing works, how the quick connects work. So we've got our line here right in back, we're going to get roughly the length that we want, to about there. When cutting your airline it's important that you use hose cutters. We've got hose cutters available here at etrailer, I'm using a more industrial pair for a larger size hoses that we do work on here at etrailer, but for quarter inch line like this we've got smaller pairs that are a little bit easier to fit in tight spaces. And we can see how that end looks there, I mean, that's just a nice, beautiful end, it's still nice and round. We didn't deform it, by crushing it, and it's nice, and 90 degree from our line. That's going to seal properly inside of our fitting there. So to insert it, it's as simple as pushing it in. That's it you've made your connection. Now let's say you've made a connection and you need to move something. So we need to disconnect it, we're just pushing it on this ring and then we can pull it out, and it's the same way with any of the hoses that have click connect fittings, including the larger ones that we tapped into over by our tank, those larger ones, just push it on the larger outer ring and pull it out. They're going to be a little harder than this one just because this is new. Those got a little dirt in there. So what you can do if you're having a hard time pushing this ring in, I use an open-end wrench, that's close to the similar size and that just helps you be able to push that ring, and especially on those dirty dirtier older RVs. So now at this point, I'm just going to go back and zip tie up any of my lines to make sure they stay away from anything moving, like your suspension or steering components, anything excessively hot, like the exhaust and that completes our installation of Demco Air Force One second motor home kit on our 2015 Tiffin Phaeton..

Customer Satisfaction Score:

Customer Reviews

Demco SBS Coach Air Kit for Air Force One Supplemental Braking System - SM99627

Average Customer Rating:  4.9 out of 5 stars   (48 Customer Reviews)

Half system replaces the necessary coach installation components for Demco SBS Air Force One supplemental braking system (9599007 and 9599019) for motor homes with air brakes.


Everything works great. Delivery up to Canada was not a problem. etrailer did themselves proud.


Everything needed to get it installed. I installed it on an older air over hydraulic coach. Only required a longer airline as the connections we're made up front.


It arrived sooner than expected. Have not installed yet.


Just what I needed to switch my brake to my new coach.


Received everything we needed to install on our coach. Instructions were very plain and easy to follow. This was my 2nd unit to install, I highly recommend these products, they are easy to install and they work very well.


I have used this system for several years and was fortunate to get a new RV, but it wasn't set up with supplemental braking. It was as easy to install as the first time and convenient that I did not have to buy the entire kit or piece it together myself. Easy from ordering to install. Thank you,


Installed on my 2016 Meridian & works like a champ.


The kit was easy to install and works g reat.


The new regulator on the tank did not come with information on which hoses to connect where, But I did find a etrailer online video that gave that information. The install went pretty fast.


smi air brake for tow cars is the best brake system for a tow car and diesel pusher or class a motorhome with air brakes bare none ,once its installed all you do is hook up plug in and your off.I price checked multiple sources and etrailer had by far the best price.


Bought another Allegro Bus that didn't have towing setup i had on my towable.
Was advised as to which kit to order, installer had no problems installing it. Everything went smoothly. Great service


I haven't installed the system yet, but I have given 5 stars for the OUTSTANDING customer service I received from etrailer. Shortly after I placed the order, I found the item listed for about $75 less on [another] store, and I submitted a claim under their 110% price guarantee policy. Even though the lower priced item had a fixed price and wasn't up for auction, I still didn't really expect etrailer to honor their pledge because the item was listed [online] Much to my surprise they honored their policy without question and credited the 110% my purchase almost immediately. The item was well packged and arrived quickly. I cannot recommend this company highly enough.


Thank you for sending the Air Force One supplemental braking system quickly. Placing the order was easy. I did appreciate the free shipping. In the near future, I will make an effort to check on any RV parts that your company has to offer.


Would have been 5 stars, but no instructions. We'll have to find them on the web. Etrailer price pledge saved $30.

If you click the provided link, you can see the installation instructions for the whole SMI Air Force One kit, the instructions specific for mounting the air system on the Coach begin on page # 8.
-- Etrailer Expert Mike L - 04/21/2018


Fast delivery and great customer servic e!!!


Works great


I received the product quickly and the product was every thing they said it was. Installation was easy and the brake system works great.


Communication was great ,, Great service, good people to talk to .. Feel like if I have a question they would take the time to answer.. Thanks


Great product. Installed and working gr eat.


Product arrived when promised and has been installed. So far it seems to be maintaining air pressure but have not yet tested it while traveling and towing the Jeep. It replaces the part that worked well for ten years so should be good.


Demco coach air kit was exactly as advertised and performs flawlessly


Product was 3 weeks late shipping as factory supplier delayed providing product but I was kept informed all the time and when shipped was delivered within 3 days. Very pleased with the service.


Looks like a decent product as i havent installed. Howver no instructions for install in box. But I found instructions on smi web psge.


Best braking system and easy install


Always good prices. excellent customer service on the phone. item delivered as promised.

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