1. Accessories and Parts
  2. Demco
  3. Tow Bar Braking Systems
  4. Second Vehicle Kit
Demco SBS Second Vehicle Kit for Air Force One Supplemental Braking System

Demco SBS Second Vehicle Kit for Air Force One Supplemental Braking System

Item # SM99209
lowest price pledge
Retail:$1,164.61
Our Price: $949.00
You Save: $215.61
Accessories and Parts
This item qualifies for Free Shipping
Shipping Weight: 9 lbs
Quantity: 
Demco SBS Second Vehicle Kit for Air Force One Supplemental Braking System Second Vehicle Kit SM99209
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

In Use/Installed

Customer Photos

Second vehicle kit includes everything needed to tow your other vehicle without having to install an entirely new Demco SBS Air Force One supplemental braking system. Includes wiring, air lines, and hardware. Call 800-298-1624 to order Demco accessories and parts part number SM99209 or order online at etrailer.com. Free expert support on all Demco products. Guaranteed Lowest Price and Fastest Shipping for Demco SBS Second Vehicle Kit for Air Force One Supplemental Braking System. Accessories and Parts reviews from real customers.
  • All Info
  • Reviews (36)
  • Q & A (35)
  • Videos (14)
  • Photos
  • Why etrailer?

Demco Accessories and Parts - SM99209

  • Tow Bar Braking Systems
  • Second Vehicle Kit
  • Demco

Second vehicle kit includes everything needed to tow your other vehicle without having to install an entirely new Demco SBS Air Force One supplemental braking system. Includes wiring, air lines, and hardware.


Features:

  • Lets you use your Demco SBS Air Force One supplemental braking system with an additional vehicle
    • Works with Air Force One system SM99243 (9599007) - sold separately
  • Includes everything you need to set up your other vehicle for towing
    • RV-side kit (SM99627) sold separately
  • Made in the USA
  • 5-Year warranty


6271 Demco SBS - (Formerly SMI) Additional Vehicle Kit for Air Force One Supplemental Proportional Braking System

Replaces Demco SBS SM99209 and SM99213





Video of Demco SBS Second Vehicle 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 Second Vehicle Kit Installation - 2020 Jeep Wrangler Unlimited

Shane: Hi. I'm Shane with etrailer.com. Today I'm going to walk you through how to install Demco's Air Force One second vehicle kit. The second vehicle kit is going to be just the vehicle side. What it's going to do, it's going to allow your vehicle, when it's being flat towed to apply the brakes on its own. So the vehicle, it's not only slowing but stopping itself.

We're not relying on the brakes on the RV to slow and stop both vehicles. Any of us that have RVs know that replacing the brakes on your RV is very expensive.Having a braking system on your vehicle is going to be required by law in any state, for a vehicle that's being flat towed behind a motorhome. It's also going to be one of the five main components in any vehicle being flat towed. The other four are going to be your safety cables, your tow bar, your wiring, and your base plate. The Air Force One is going to be designed for motorhomes with air brakes.

What it does, is it gets air pressure from the brakes on the motor home, sends it through the airline, up into the unit, from the unit through airline tube that goes in. The air line tube is connected to the actuator, mounted on the brake pedal arm, giving it pressure to apply the brakes in the vehicle.It's also going to come with a secondary safety device, which is going to be your breakaway switch. If ever the vehicle comes disconnected from motor home, what it's going to do is this cable that is connected to the hitch on the motorhome, is going to pull this pin. When it pulls this pin, the built up pressure in the unit inside the vehicle is going to apply the brakes on the vehicle to bring it to a safe stop. Now that we've gone over some of the features, let's walk you through how to get it installed.To begin your installation, you need to find a place to mount your operating unit.

There's a couple of different places you can put it. You can put it under the driver's seat. You will have to take the seat out to do it. You can see here I mounted mine on top of the fuse panel lid. Alls I did is took the lid off, lined it up, drill a couple holes, and ran a zip tie through it to hold it in place.

Holds it very securely. Next you need to mount your breakaway switch in your L bracket with your air fitting on it. I mounted mine to the plate that comes with the base plate for this vehicle, and just bolted it right to the factory bolt holding this rack guard on.My L bracket with my air fitting, I just use self tapping screws, went right up through the rock guard. On the back of the breakaway switch, route them behind your plate or your guard, you're going to have a blue wire and an orange and black wire. Route them up towards your operating unit. You will have to extend these because they're not going to be long enough to make it all the way up. One of the black wires coming off your operating unit is going to connect to the blue wire going down into your breakaway switch. The orange and black wire, which you can see here, I extended it with another black wire, is going to connect to a brown wire and into a fuse holder that, once you get everything connected, will connect to, or attached to the positive side of the battery.Take your brown wire, you're going to route it over to the driver's side. It's going to go through a grommet inside the vehicle in the driver's side floorboard. With our second black wire that's coming off our operating unit, we need to ground up. There's actually a factory ground right here on the side of the vehicle. It doesn't matter which black wire you use to do what, you just want to use one as a ground and one going to the blue wire to the breakaway switch. Your air fitting. Your kit's going to come with air line tube. Go off the back of it, there's going to be an L bracket, route it through the back of your rock guard.I routed it up the same way I did my wiring, behind the headlight, right through here, and it's going to go to the air in port. You want to make sure when you cut these lines that the end is cut flush. It's not at an angle, because you don't want any air leaks. You're going to take the other part that you cut off, put it into the air out. You're going to route it around same way you did your brown wire, it's going to go in through the grommet, which is going to be right here, into the driver's side floorboard. Keep in mind this grommet is not going to be there if you have a manual transmission. You will have to find another way to get inside the vehicle.On the Jeeps, there's a lot of plugs in the floorboards that you can get through there. Automatic, you can go right through this one. So that's where your lines are going to come in from your engine compartment into the driver's side floorboard. Next, from inside you need to mount your indicator light. This is where your brown wire and your air line tube, we're going to come in from the engine compartment into the driver's side floorboard. After that, you need to mount your actuator onto your brake pedal arm.Your kit is going to come with longer bolts. It is going to require those longer bolts to put it in. You're going to have a small bracket that's going to get mounted to the firewall. You need to mount that on the firewall. The cable that's coming off the back of the actuator needs to have at least a quarter inch of play in it, so that it's not applying the brakes all the time. It's going to come with self tapping screws. They're pretty long. I suggest getting a little bit shorter ones to install that. Once this is in, you want to make sure that the actuator is going in a straight line to this bracket. And it looks like actually if I push on this, this is a little bit low, so what I'm going to do is I'm going to end up loosening this and just rotate this up enough where it's going more in a straight line than what it is.You also want to make sure that your actuator is up high enough, that when you put your foot on the brake, you're not going to hit the actuator itself. Air line tube, once you get it mounted, cut it to length and you're going to put it into this L bracket. You want to make sure that this has a loop in it. It's not kinked anywhere. While it's coming out of here, and going out of the grommet. You're going to have your switch, which is right here on the end. It's probably going to be a little bit easier if you mount that because it's got a little bitty flat head screw that goes in right here. Probably a little bit easier to mount that on the actuator first before you put your actuator in.Once you get that, your read switch is going to have three wires coming off it, brown, blue, and black. Brown wire is going to go to the brown wire coming in from your grommet from the engine compartment. After that, you're going to have the blue and black wire. You need to mount your indicator light. This is what your indicator light is going to look like. It can be mounted anywhere on your dash. You just want to be able to see it from the camera on the back of your RV. Most of the time we will mount them behind the rear view mirror, but if we mounted it here, you can see this shading that's on the glass, you wouldn't be able to see the light. So I mounted it here. Routed my wire right below, tucked it in right underneath of this speaker cover, came right around the corner of the dash. There's a panel right here that pops out. I popped the panel out, routed this back behind and then tucked to underneath the dash.When connecting your indicator light to your read switch, you remember you have a blue wire and black wire left on your read switch. Your indicator light is going to have a red and black wire. You're going to connect the red wire to the black wire, black wire on the indicator light to the blue wire on the read switch. Keep in mind the end of these wires have a little prong them. Don't cut those off because these wires are very thin. Crimp them inside the butt connectors that come in the kit. Going to make it a lot easier to make that connection.Once you make this connection, I suggest putting a little bit of tape around these. You can bundle them up and zip tie it up underneath the dash where they're out of the way and they won't get damaged or pulled apart. The next thing you need to do, is you're going to have vacuum line like this. It's going to come into a large loop. Going to go about three inches, doesn't have to be exact. You're going to cut that line. You're going to put a check valve in. You notice that the black side is going towards the unit. Green side is going the opposite direction. Put the check valve in. I ran mine across. Zip tied to this factory line here, came all the way across, and looped it right here.We want the wine that's coming out of our brake booster and it runs right here. I looped it and put it into my T-fitting. I've actually made this to fit in between, so we had to cut off the plastic factory vacuum line here and down a little bit farther. I'm actually going to walk you through how I actually made this so you get a little bit better idea. In your kit, you're going to have a T fitting. You're going to take part of your vacuum line, you're going to put a piece on each end. As a rule of thumb, you can see the three lips there, you want to make sure that this line is covering those three lips on each side.You're going to take the next check valve, you're going to put the green side in, black side facing out. You're going to add another piece of hose on the end. You're going to have clamps in your kit. Once you cut that section out, you want the black side, or that check valve going towards the engine, green side going towards the brake booster. You're going to put your clamps on first, spray the plastic hose with a little bit of soapy water. Sometimes you may need to stretch this line out so you take some needle nose pliers in there. You can kind of stretch that line out, slide it on, slide your clamp on and tighten this around this plastic line.Don't tighten it so much that it pinches this and causes a vacuum leak. You're going to do it up here and down below. And notice here you can see it, this is where my check valve is. Black side again is going towards the engine. Vacuum line that I have run across, I looped it. I want to make sure I don't have any kinks. I looped it, and put it into the bottom of the T, so it potentially sits like this, right here. Once you have everything installed, go ahead add on your ring terminal, make your connection, and then put your fuse in the fuse holder. Once you have everything connected, go ahead and clean up your wiring. Set up your vehicle behind your motorhome. Go ahead and test out your braking system, make sure everything's working together.


Customer Reviews

Demco SBS Second Vehicle Kit for Air Force One Supplemental Braking System - SM99209

Average Customer Rating:  4.9 out of 5 stars   (36 Customer Reviews)

Second vehicle kit includes everything needed to tow your other vehicle without having to install an entirely new Demco SBS Air Force One supplemental braking system. Includes wiring, air lines, and hardware.

- SM99209
by:

Installed the Air Force One (AF1) in a 2017 Wrangler Rubicon. This replaced a RoadMaster Even Brake system. Love that the AF1 is so small and completely out of the way. Love that we don't have to cart the brake controller in and out every time we hook up and disconnect. It's so much easier just attaching one air hose and away you go. I created a mounting plate from 3/16" aluminum plate and mounted it under the hood. (See pictures). Installation was pretty simple. Just make sure you take your time to align the cable correctly from the pneumatic control. I would also recommend using a through bolt through the Jeep firewall with fender washers as the firewall is pretty flimsy and I was worried the provided sheet metal screw wouldn't hold. It took a couple of test runs to get the cable adjusted properly but I haven't touched it since then. We've done 50 or more hookups and disconnects since initial installation and everything has been flawless. Would definitely buy this system again.



- SM99209
by:

Works great. I had a shop complete the installation on my Mini Countryman.



- SM99209
by:

Easy to install. Breakaway doesn't work as advertised on my GMC truck.



- SM99209
by:

Super happy with this device and the the overall experience with Etrailer. The video’s Etrailer provides to help with install were spot on and made it really easy for a diy project.



- SM99209
by:

I installed this SMI Air Force One braking System on a 2017 Jeep Wrangler Sahara Unlimited. I watched and then followed the etrailer video. It was an easy install and the video was spot on. My coach already had the air tank installed, so I just had to buy the Second Vehicle Kit and the Air Jumper.


Comments
Ive put 11,000 miles on this towing set-up in the last year. Still loving it.
F. B - 07/18/2019



- SM99209
by:

We bought a Motorhome that had this braking system installed but we did not get the parts from the towed vehicle. This second vehicle kit was perfect for that. Etrailer had the best price and it was delivered fast. I will continue to use Etrailer.



- SM99209
by:

very prompt service and delivery to my door step! Truly a easy process.



- SM99209
by:



- SM99209
by:

Another fast delivery. Install was easy and the product works very well. Great quality.



- SM99209
by:



- SM99209
by:

Decent product but I think it's over priced. Not all parts needed for the install were present. Also, I broke two of the bolts tightening them down.....should be better quality and there could be a few extra included. Hopefully it works well.



- SM99209
by:



- SM99209
by:

Good



- SM99209
by:

Complete package of components to prepare a second vehicle braking system for towing behind a diesel Motor Home with SMI. Also eTrailer was fantastic in getting the product to us and follow-up support. Great company to work with!



- SM99209
by:

I had a few questions about the "Air Force One Second Vehicle Kit" and e-mailed them on Sunday. Monday morning I got a response and gave them a quick reply. Minutes later another quick response. The staff at E-Trailer went over and beyond with their knowledge and had all the answers. I ordered the kit Tuesday morning and was on my doorstep Thursday afternoon. Hats off to the "E-Trailer Staff" for the quick shipment.



- SM99209
by:



- SM99209
by:

Ordered SMI Air Force One 2nd vehicle brake kit. I was concerned that it would not be the current model but was assured it would be after a quick. Product arrived quickly and was in fact the latest model. Price was great, service superb. Couldn't be happier.



- SM99209
by:

Excellent product. It's fairly easy to install if you're mechanically inclined. It is the best system to use on your toad if you have a diesel pusher. Installation difficulty is a 3 with 5 being the hardest. That's depending on what the model of vehicle it is being installed in. Great company. Their customer service is outstanding.



- SM99209
by:

This transaction went smoothly, This is for an replacement item that was lost in Harvey flood. Worked great on my H3 Hummer for braking. Plan on buying another hummer for TOAD. Had fast delivery. Have done business with etrailer in the past. Haley was very helpful and pleasant to deal with. Thank You



- SM99209
by:



- SM99209
by:



- SM99209
by:



- SM99209
by:

Very satisfied with the order. Shipping was very quick. Everything was in order. One of the few retailers that advertised the SMI second vehicle kit. I wouldn't have known about it if I hadn't seen on their site. Saved me $300. Glad I bought from etrailer. Will buy from them again.



- SM99209
by:

All the items were exactly as anticipated and arrived when expected. etrailer sent me several emails keeping me appraised of the order status and to check that the package arrived ok. Excellent customer service.



- SM99209
by:


26
37
Show More Reviews

Ask the Experts about this Demco Accessories and Parts

Do you have a question about this Accessories and Part?




  • Why etrailer.com?

    At etrailer.com we guarantee:
  • Highest quality accessories and parts for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate accessories and part information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Andrew K
Video by:
Andrew K
Employee Kathleen M
Video by:
Kathleen M
Employee Dustin K
Video by:
Dustin K
Employee Michael B
Video by:
Michael B
Employee Jacob H
Video by:
Jacob H
Employee Aidan B
Video by:
Aidan B
Employee Jeff D
Installed by:
Jeff D
Employee Cole B
Installed by:
Cole B
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Laura H
Written by:
Laura H
Employee Randy B
Test Fit:
Randy B
Employee Andrew S
Test Fit:
Andrew S
Employee Shane H
Test Fit:
Shane H
Employee Robert C
Test Fit:
Robert C
Employee David F
Test Fit:
David F
Employee Ryan G
Test Fit:
Ryan G
Employee Clayton O
Test Fit:
Clayton O
Employee Sarah W
Updated by:
Sarah W
Employee Jenny M
Updated by:
Jenny M
Employee Kristina F
Updated by:
Kristina F
Employee Matthew E
Updated by:
Matthew E

At etrailer.com we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.