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Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional

Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional

Item # SM99243
Our Price: $1,329.00
You Save: $1,824.49
Tow Bar Braking Systems

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Product Expert Mike S

Is this right for you? Product Expert Mike S says:

Yes, if you:

  • Have a motorhome with air brakes
  • Don’t have time to waste setting up a portable system before every trip
  • Tow a nicer or newer car and want the most precise braking possible

No, if you:

  • Upgrade your towed car every few years
  • Are hesitant to make any modifications to your motorhome
This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready. Great Prices for the best tow bar braking systems from Demco. Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional part number SM99243 can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (249)
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  • Why etrailer?

Demco Tow Bar Braking Systems - SM99243

  • Brake Systems
  • Air Brakes
  • Proportional System
  • Fixed System
  • Demco
  • One Time Set-Up
  • Power Assist Brake Compatible

This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready.


  • Supplemental braking system applies towed vehicle's brakes in proportion to braking action of RV
    • Towed car's brakes are activated at the same time and with the same intensity as those in your motor home
  • Truly proportional system uses the air pressure from your RV's brakes to apply the brake pedal in your car
    • Coiled air hose connects air assembly in RV to operating unit in towed car
  • No false braking
    • Coach air brakes must be activated for system to apply towed car's brakes
  • One-time setup - no need to remove or to activate each time you tow
    • Operating unit and actuating cylinder stay hidden so everything is out of your way when you are driving
      • Low-profile design of operating unit allows for more room in the engine compartment of towed car
      • System automatically functions when towed vehicle is connected to RV
  • LED coach notification system illuminates when the towed vehicle's brakes are applied
    • Connects to towed car's brake light switch to ensure proper reading
  • Vacuum-assisted function of towed car is activated with air from the coach brakes
    • Less force is needed to move the brake pedal in the car, resulting in more natural braking and less risk of damage
    • Compatible with vehicles that have continuous-power-assist brakes
  • Breakaway included
  • System meets FMVSS safety guidelines for motor homes that use air brakes
  • Necessary installation components and an instructional CD included
  • Made in the USA


  • Application: motor homes with air brakes
    • Can accommodate air-over-hydraulic brakes - additional 1/4" DOT air line (not included) may be required
  • Coiled air hose length when fully stretched: 7'
  • Breakaway cable length when fully stretched: 7'
  • 5-Year warranty

A supplemental braking system is a must when towing a car or truck behind your RV. Without it, the weight of the towed car can create a safety hazard, strain your RV's brakes, or affect your RV's warranty. Most states require a supplemental braking system.

Automatic, Truly Proportional Braking

Air Force One is a proportional braking system. When you apply the brakes in your motor home, the system will engage your towed car's brakes at the same time and with the same pressure as those in your motor home, creating synchronized braking.

To achieve this proportional braking, Air Force One ties into your coach's air brakes. The patent-pending process uses air pressure from your coach's brakes to depress the brake pedal in your towed car. The result is uniform, real-time braking that mirrors the slowing or stopping action of your coach. Whether you lightly tap the brakes in your RV or apply them hard in a panic situation, your towed car's brake pedal will be applied in the same manner.

Many other proportional systems activate the towed car's brakes based solely on inertia. With this kind of setup, any activity that affects the forward momentum of your towed car - from the coach actually braking, to driving over a pothole - can activate the supplemental braking system and apply your towed car's brakes. This potential for false braking, which can occur simply from driving over uneven terrain, can create a rough ride for you in the RV and can also wear out your towed car's brakes over time. Air Force One is different, though. Because it is tied into your coach's brakes and is not dependent on inertia, this system activates only when you apply the brakes in your RV, so there is no false braking.

Permanent Installation with Concealed Components

Once you install the Air Force One system, it stays concealed and out of your way - both in the RV and in the towed car. Unlike systems that require you to keep the actuating box under the seat or in the trunk of your towed car, Air Force One does not take up valuable storage space inside of your car. And the components that install on your RV all remain hidden beneath the vehicle so that no room is taken up in its interior either. Because the entire system installs permanently, there is no need to constantly set up and remove this system. You never have to worry about where to store a bulky actuator box when you're not towing. And while most of the components do remain on your vehicle and RV at all times, none of them will interfere with normal driving or braking.

Coach Air Connection Assembly

Because Air Force One uses air to activate, it is a natural choice for diesel motor homes that have air brakes. The coach air connection assembly taps into your RV's air brakes and delivers the air necessary to activate the towed car's brakes through the included coiled air hose. The valves on the coach air connection assembly ensure precise airflow.

Pressure Protection Valve

A 1-way check valve collects air from your RV's brake lines so that it can power your towed car's brakes. This pressure protection valve also ensures that your RV's air lines maintain the same amount of pressure so that the braking in your RV is not affected.

Relay Valves

Metered air from the coach's brakes connects to a service relay valve. This relay valve collects air from your RV's brake lines so that it can power your towed car's brakes. When you activate the brakes in your RV, the delivery relay valve releases the appropriate amount of air to the operating unit in your towed car.

The coach air connection assembly is best mounted in a location on the RV where the air lines will not be near direct heat sources or moving parts, such as in front of the rear axle.

Note: Air Force One is designed for motor homes that have air brakes, but it will also work with RVs that have air-over-hydraulic brakes. Additional parts (not included) may be required for installation on RVs with air-over-hydraulic brakes.

Operating Unit

The operating unit, which mounts in your towed car, receives air from the coach air connection assembly. The unit then diverts a matching amount of air through a hose to the actuating cylinder that mounts on your towed car's brake pedal. That air activates the cylinder so that it applies proportionate braking pressure.

The unit goes under the hood of your towed car, so it is out of your way and always ready. Because this system is a universal fit, you can remove it from your towed car and reinstall it in a different car or truck if needed.

Actuating Cylinder

Small Cylinder

The actuating cylinder depresses your towed car's brake pedal upon receiving the air that is delivered from the operating unit. This small cylinder stays mounted on the arm of your towed car's brake pedal at all times and will not interfere with braking while driving.

Actuator on Pedal

Mount this cylinder so that it is perpendicular to the firewall when you depress the brake pedal. A clamp anchors the actuator to the firewall.

To connect the actuating cylinder to the operating unit, you will need to run the included air hose through your towed car's firewall. You can usually create the necessary, small opening without drilling. In most instances, you can cut a slit in the hood release cable grommet. Simply cut the end of the air line at an angle to poke it through the slit.

Coiled Air Hose Connection

Coiled Air Jumper

The coiled air hose, also called a jumper, connects your towed car to your RV by connecting the operating unit to the coach air assembly. When you are ready to hitch up your car and tow it, simply hook up the coiled air hose at the same time as you hook up your tow bar.

Vacuum Pressure Creates Smooth Braking

Normally, when you activate the brakes in your vehicle, a vacuum multiplies the pressure you apply to your brake pedal, creating the force necessary to stop the full weight of the moving car. On most cars and trucks, this vacuum-assist function does not work when the engine is off. As a result, many supplemental braking systems on the market have to use an excessive amount of pressure to effectively depress the towed car's brake pedal.

Air Force One reactivates the vacuum-assist function of your car's brakes when it's being towed, even though the towed car's engine is not running. As a result, the actuating cylinder does not need to apply extreme force to the brake pedal to achieve proper braking. The operating unit ties into your towed car's vacuum line with a tee so that it can use the air pressure from your RV to create the vacuum your car needs to brake gently. As a result, no additional vacuum pump is required to create the vacuum-assist function for your towed car's brake pedal. Air Force One will replenish your towed car's vacuum after each braking event so that you will get smooth, even braking every time.

Built-In Safety Features

AFO Light in Towed Car

Most supplemental braking systems have methods of letting you know you when the system itself is activated, regardless of whether the towed car's brake pedal is depressed. Such setups leave opportunities for false notification. Air Force One's system is different. This system's LED monitor connects to your towed car's brake light switch. When your car's brake light goes on or off, so does the notification light. So you can tell whether your car's brake pedal is depressed.

Air Force One Monitor Install

You can attach the monitor light to the back of the rearview mirror of the towed vehicle . This way you can see the light from your RV's backup camera or rearview mirror.

AFO Breakaway

The breakaway system ensures that your car will come safely to a stop if it accidentally detaches from the RV while you are towing. A switch mounts to the front of the towed vehicle . This switch - which is wired into the operating unit - includes a pin that connects to your RV's hitch receiver with a breakaway cable. If the car separates, the cable pulls the pin from the switch, causing a signal to be sent to the operating unit. A reserve air supply will then apply your towed car's brakes. This system also has "total coach protection" built in. If there is separation, the RV's air supply is sealed off, so its brakes will continue to function as normal.

Air Force One meets Federal Motor Vehicle Safety Standard (FMVSS) guidelines requiring that supplemental braking systems use a separate air supply and activation relay valve.

9599007 AFO115 Demco SBS - (Formerly SMI) Air Force One Supplemental Proportional Braking System

Replaces Demco SBS SM99202 and SM99243

Installation Details SM99243 Installation instructionsAlternate Instructions SM99243 Installation instructions

This Product Fits The Following Vehicles

Customer Satisfaction Score:

Customer Reviews

Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional - SM99243

Average Customer Rating:  4.9 out of 5 stars   (249 Customer Reviews)

This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready.


I believe the AFO is the best supplemental braking system for air brakes on the market today. Probably the most expensive also. A lot of work to install but a good system that is truly proportional and safe to use with an air brake system.

We have used our AFO for over 12,000 miles towing a 2018 Chevrolet Colorado. It seems to be working fine but is really hard to know for sure. It is difficult to see the LED light strip in the camera during bright daylight. When I installed the AFO, etrailer was very helpful even returning my call on a Sunday. I also added a plastic stub next to the connectors on both the RV and toad that very conveniently stores the plastic cover when the brakes are not connected so they do not get lost. I tried to contact etrailer with my simple improvement but no one seemed interested.
Bruce P - 12/14/2021

2014 Honda CR-V

AF1 is amazing so far. I did the installation by myself. I have a 2014 Honda CR-V and bought it for towing. Watching the video helped me through it. The car installation portion was pretty straight forward. The video is better than the instructions overall, but I read through the entire instructions before beginning. I was able to install the RV tank without putting the rig on a lift. Depending on how big you are and flexibility, it can be done with the RV on the just takes longer. Also, I would recommend knowing where you are going to mount your RV tank. I mounted the tank near the rear and didn’t have enough brake tube after doing the car. Picked up an extra 20 ft at Autozone or order the tube with etrailer.

The customer service center is very helpful too. Many thanks to Mariah for the outstanding assistance. Finally, I would say that if you order the brackets to mount the emergency brake away for your car, you may have to cut them down with a grinder. It is so much nicer not putting the brake buddy in the car now. Looking forward to enjoying it on trips. I drove the rig about 20 miles yesterday, and the light came on and I honestly couldn’t tell the car was back there other than looking in the video and seeing the light on the car during braking. Highly recommend this unit.

5.0 Product is working great! No issues. Minor adjustment to brake cable after a year. It took 5 mins.
Darryl W - 07/28/2021


I wouldn't use anything else! Once this system is installed it's literally plug-and-play. Nothing to move or install into the car, each time you tow. Just plug it into the coach's air break system and you're done. Install video from etrailer made it even easier to complete.

You do need a bit of mechanical guidance/assistance as you're connecting to both your vehicles and coaches breaking system but it has worked flawlessly for over 11,000 miles and in some pretty intense traffic.


I installed it myself, followed the eTrailer installation video. I have used it a year, works great, have put over 3000 miles on it. No issues. Struggled with using a portable brake system and decided to do it right. It was the right choice.

Perfect, way better that the portable device
Jay - 07/23/2022


It would be nice if the instructions told how the AFO was designed to work in detail. Most installers have an opinion but to have it explained would be a plus. Like the small air tank in the control box etc.

2012 Saturn Relay

"Out of sight, out of mind" would be the best description I could offer for the Air Force One supplemental braking system! When properly installed, it's effective as well as quick and easy to hook up. Connect the tow bar, safety cables, safety switch cable, tow plug and air line, you're done! Five minutes at most.

I did add a couple of features to my towing system:

1. Using a relay and the extra wire in the connector to the coach, I installed the LED indicator strip on the dash of the coach; no need to rely on the back-up camera to verify operation of the brake cylinder. Coaches that have a tow connector are usually equipped with a power wire to the cab for electric brakes - this wire is a good way to get the indicator signal to the front of the motorhome.

2. I used the 12 V power connection from the coach to connect a charging wire to the car battery to ensure it would not discharge; I used an auto-resetting breaker with a rating below the glass fuse in the 12 V circuit to prevent a fuse from blowing if the charge current gets to high.

In all, a great investment! I have an article I wrote on the install if anyone is interested.

Ford Ranger

This system has worked great for my flat towing of my Ford Ranger. Had my local dealer install the system for me and have had not one single issue with the operation.

After one year and more than 10k miles have not had a single problem with the Air Force One braking system on my 2019 Ford Ranger.
Robert - 03/08/2022

2016 GMC Canyon

Vehicle 2016 GMC Canyon Diesel.
of the SMI Air Force One supplementary braking system was not too difficult. The instructions from SMI were good as was the video from etrailer. The only reason that I didn't give it a 5 star is because the air cylinder installation on the brake pedal was complicated by an unusual shape of the brake pedal arm. I eventually found a solution.
Tapping into the truck's vacuum line was a little difficult but the kit included everything I needed to T into the vacuum line and install the check valves.
All in all not a bad installation, this summer we'll see how it holds up.

Jeep Grand Cherokee

I could not find anyone in Georgia that had installed the AF1 on a Jeep Grand Cherokee and eTrailer had several videos of their installs so we drove 700 miles to get it installed by these pros. They did a fantastic job and the system is great! The main unit is in the engine bay and you have to get on your knees to see the connection to the pedal. The Grand Cherokee is heavy but I don't feel any difference when towing and it has no effect on driving the the car. I'd give it and eTrailer 6 stars if I could!


I’ve fitted it to my Jeep Wrangler then taken of and fitted to our new Jeep Grand Cherokee. Works perfectly . I had used our 53ft coach without it and in an emergency stop, was a problem stopping in the rain. Now we have had a couple of fast stops and it works great, would be without it.

2019 Jeep Wrangler Unlimited

I am missing several components.....good response in getting me what's missing. For example I had 13ft of 1/4 hose instead of 50ft. Missing the led mirror kit and connecting blue hose kits all together. I was mailed a collection of some of the parts - not a kit.

2017 Chevrolet Equinox

My installer said it was straight forward to install. I really appreciate not having to disconnect anything in the car and then find a place for it until ready to use again. It is out of sight and always ready to use.

I highly recommend this for your braking system!


I ordered an Air Force One breaking system one year ago, for my 2019 Allegro Bus 45OPP, and my 2012 Honda CR-V.
I paid $1080.00 with free shipping from E-Trailer. The unit arrived in perfect condition. I installed the system myself, in about three hours on the Motorhome. I had previously ordered a special hose/ tube cutter. The only part of the installation that was a little intimidating was cutting the correct air lines on the coach, however after viewing the installation video everything was made clear.
The install on the Honda took about two hours, I did have to call the people at E-Trailer , but they cleared up my questions.


Seems to be working well. Wife and I did our own installation and it was challenging. Standing on my head under the dashboard mounting the breaking air cylinder at the brake was tough but doable. Tapping into the air brake system on our motorhome also challenging but it all appears to do the job. Glad that job is behind us.


Love the fact that I don't have to wrestle with a bulky brake controler

2004 Chevrolet Avalanche

Pulled entire length of route 66 and then some. We had absolutely no issues with all of our etrailer equipment. Thanks for all of your help.

Jeep Cherokee

We have towed a car over 150,000 miles behind our motor home. Most of that time we used another system and always had small problems. When we bought our 2021 Jeep Cherokee we wanted to upgrade our breaking system. Our old system was also inconvenient to setup. This system is so easy to use and works great!!


We love our Air Force One braking system. The confidence it was done right by etrailer allows us to tow our 4x4 van without worrying about it!


Came with everything I needed to install it. Great quality and works fantastic!


Air force one there’s a very best braking system you can get for your tow car if your motorhome has air brakes. The etrailer did a fantastic job installing the system both on my motorhome and tow vehicle. I would highly recommend Air Force One and etrailer

2014 Jeep Wrangler

Just finished a 10,000 mile trip trailering a 2014 Jeep Wrangler with Air Force One braking system and we are very satisfied with the product. No issues or failures and once installed, it is very easy to use. We can connect and disconnect from the Air Force One and our Blue Ox towing system in 2-3 minutes.

After a year, we are still happy with the AF One. We had one issue where it didn’t work and it turned out we let a little grime get into the air fitting. Took some time to figure it out but we cleaned with compressed air and the problem went away. Lessen learned it to keep rubber covers on the air fittings when not in use.
Joe T - 05/17/2020

2017 Jeep Wrangler

Very nice unit, very easy install on a 2017 Jeep wrangler Rubicon Recon and and Great Support eTrailer !! Super Fast Shipping !!!

The Air Force One unit has been great. Very easy to use and hook-up is a snap.
FJ40 - 01/19/2022


Product works good. No longer have to put the old box between the seat and the brake pedal and hook up to brake petal. So easy to hook up. Be sure your air hose connections are are secure. Unit does not work when one end of air hose is on the ground. I know from experience. Would suggest ordering an additional air hose just in case you need it


Installation was easy, compact and out of the way. Had a little problem finding controller location due to clearance. Ended up using velcro on top of the fuse box to hold the controller in place.

2016 Jeep Wrangler

SMI Air Force One was the choice I made when we outfitted our 2016 Jeep Wrangler Unlimited last year. I can honestly say, without any hesitation,...this was the best choice ever. The installation was very straight forward. I was reluctant to cut my coaches brake lines...but the technicians at SMI were very helpful. I emailed them a picture of the brake lines that I had identified per the instructions, and wrapped a piece of colored electrical tape around the lines to identify them. The SMI techs wrote back within 20 minutes and confirmed that I had correctly chosen the correct air lines for splicing into. The fittings where a breeze to install. The system has performed flawlessly...and it works so well ---- if it weren't for a video camera view on my dash...I wouldn't even know the Jeep was back there.

When I go to hook and unhook the Jeep. I keep my components in a canvas bag. It contains my Safety cables for the tow bar, lighting umbilical, and the two SMI parts...a coiled quick connect air line, and a safety breakaway cable. The other components of the system stay in lugging them around. They are totally out of sight.

If you have a coach with Air Brakes...this, in my opinion, is the best thing going. Proportional braking...directly metered by your coaches signal line. The system is robust...and includes it's own ping tank, and D.O.T. approved metering valve. I feel it's the safest...and best performing braking system built for a towed vehicle PERIOD.

Show More Reviews

See what our Experts say about this Demco Tow Bar Braking Systems

  • Best Supplemental Braking System to Flat Tow a 2006 Hummer H3 Behind a Motor Home with Air Brakes
    The Blue Ox Patriot and similar box style supplemental braking systems are not recommended for your 2006 Hummer H3. I recommend going with the Air Force One # SM99243 because your Monaco Dynasty has air brakes. With air brakes you want a system that doesn't activate the H3's brakes based on the brake lights of the RV. It can cause false braking and therefore more wear on the Hummer. You won't have this problem with the Air Force One. I've linked a sample install video for on a different...
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  • Supplemental Braking Recommendation for Flat Towing a 2016 Ford F-150
    Our installers here do not like the Blue Ox Autostops that you referenced much at all. They don't seem to apply enough braking power and the install is somewhat difficult. Since your Newmar Essex has air brakes the best system for you is the Air Force One # SM99243. It prevents false braking on the F-150 because it doesn't use the coach's brake lights for activation like a lot of other systems do.
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  • Air Force One Supplemental Braking System Actuates Vehicle Brakes When Not Attached to RV
    I spoke with my contact at SMI, the manufacturer of the Air Force One braking system. He had a few possibilities that he recommended you have checked. Where the cable that joins the actuator cylinder on the brake pedal, make sure that there's about 1/4 to 1/2 an inch of slack in the cable. Also, if the vehicle has adjustable pedals, make sure that the pedals are move as close to the seat as they'll go when the tension on the cable is set. This procedure is outlined in Step 7 of the installation...
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  • Installing SMI Air Force One Supplemental Braking System on 40 Foot Dutchcraft on Spartan Chassis
    When installing the SMI Air Force One Supplemental Braking System For Motor Homes with Air Brakes # SM99243 you will need to find the supply air line and the metered air line. On the Dutchcraft motor home on the Spartan Chassis the larger 5/8 inch line is the supply air line, and the smaller 3/8 inch line below the supply air line is the metered air line. I have attached a photo showing witch line is the supply and which line is the metered.
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  • SMI Air Force One Brake System Air Line Connection in Coach Recommendation
    In the install instructions for the SMI Air Force One system part # SM99243 that you referenced the correct line to use for the Spartan Chassis is pointed out. I attached that picture. The line to use is the coach's supply air hose. This line goes from the service relay valve to the braking air tank. It is 5/8 inch in outer diameter. This line is normally green and should not be confused with the treadle valve hose which is 3/8 inch in diameter.
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  • Installation Video for SMI Air Force One Braking System for MHs with Air Brakes SM99243
    My contact at SMI Manufacturing advised that their Air Force One Supplemental Braking System for Motor Homes with Air Brakes, part # SM99243, will soon again have an enclosed installation video disc. Current production does NOT have the disc enclosed as SMI is in the process of preparing an updated installation video. We do have videos that we produced here at etrailer that show the installation process. I have linked those for you. One shows installation in a pickup, the other in a SUV.
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  • Best Mounting Location for SMI Air Force Braking Controller SM99243 in 2015 Ford F-150 Platinum
    My technical contact at SMI was quite familiar with your installation question that concerns your non-removable front grille. In trucks like your 2015 F-150 Platinum the best location to install the SMI Air Force controller unit is right on top of the plastic cover over the engine intake. This cover can be drilled to allow mounting of the controller and then be re-installed.
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  • What are the Measurements of the Box Part of the Air Force One Braking System
    The SMI Air Force One models we have in stock, # SM99243, are indeed the new AFO115 models and not the old, larger AFO108 models. The overall length is 10-1/2 inches from handle to handle but the actual box part is 8-1/2 inches. It is 5-3/8 inches wide and 1-1/4 inches tall.
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  • Compatibility of SMI Manufacturing Air Force One Supplemental Braking System with 2004 Jeep Liberty
    According to SMI Manufacturing, their # SM99243 Air Force One is compatible will any vehicle, which means it'll work just fine on your 2004 Jeep Liberty. I've linked you to some flat towing help articles you might find helpful.
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  • Does Air Force One Supplemental Braking System Come With Coach Kit
    Yes it does! The Demco SBS Air Force One Supplemental Braking System for Motor Homes with Air Brakes # SM99243 does come with the coach air kit and LED coach notification system which tells you when your towed vehicle's brakes being applied. I have added links to a video review and install for you to check out as well of the Air Force One Supplemental Braking System # SM99243.
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  • Can Demco Air Force One Fit 2021 GMC Sierra 1500 Diesel
    I checked with Demco and they do not have the versions of your 2021 GMC Sierra 1500 with the diesel engines excluded with the Air Force One # SM99243 so this would fit and work great. There would be enough room for the canister to fit. This uses vacuum to build a vacuum in the air tank that this kit installs on your vehicle and then that same vacuum activates your brake system so that the line that pulls the pedal can do so relatively easily.
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  • Monitor Light In Motorhome and Vehicle Brake Lights On With SMI Air Force One
    I spoke to my contact at Demco about the issue you are having with the SMI Air Force One Supplemental Braking System part # SM99243. They informed that if both the monitor light and toad's brake lights are on while driving without the motorhome's brakes depressed then the cylinder is most likely engaged just enough for you not to notice that the brakes are being applied but enough for the system to detect it. The cause for this is due to not having the proper slack on the cable in between...
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  • LED Monitor on Demco SBS Air Force One Supplemental Braking System Stays Illuminated
    You'll want to review the installation of the actuator read switch for the LED monitor, as incorrectly installing it can cause it to ground out, in which case it'll stay illuminated all the time. The procedure is described in step 7, on page 25 of the instructions. I've inked you to the installation instructions for the Air Force One # SM99243 braking system.
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  • Can Air Force One Supplemental Braking System Install in Hummer H3
    Yes, we have checked with SMI and they have confirmed that the Air Force One part # SM99243 that you referenced is a confirmed fit with the Hummer H3s like what you have. Since this system is designed to operate the brakes of a vehicle with the assist function of the vehicle active (either electric or vacuum) this does not require any additional steps for your setup.
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  • Who Can Install SMI Air Force One Braking System
    We do not have any particular installers that we recommend where you live in Indiana. With that being said a local mechanic with experience or an RV dealer with a service department should be able to install the SMI Air Force One Braking System # SM99243 that you referenced without issue. I simply recommend visiting a local mechanic with the installation instructions I attached. This way the shop will be able to see if it's something they are comfortable doing and they should be able...
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  • Estimated Installation Time for SMI Air Force One Braking System
    I reached out to my contact at SMI and he said that for both the RV and your 2017 Chevy Silverado you're looking at a total install time of around 5 to 6 hours for the Air Force One Braking System # SM99243. I have attached an installation video on the 2017 Silverado that you can use for reference along with the written manual.
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  • Best Braking System for Flat Towing 2015 Jeep Wrangler Unlimited with 2015 Tiffin Allegro Bus 45
    The best supplemental braking system for your 2015 Jeep Wrangler Unlimited that works with the air brakes from your 2015 Tiffin Allegro Bus 45 is the SMI Air Force One # SM99243. This is a proportional braking system which means the brakes on your Jeep will apply at the same time and with the same intensity as the brakes on your Allegro plus it is a permanent installation that installs out of the way so you won't even realize it is still there when you aren't flat towing your Jeep. In fact,...
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  • Supplemental Braking System Recommendation for 2007 Jeep Liberty Towed by Air Brake Motorhome
    For you application we have the SMI Air Force One kit part # SM99243 which works really well. This is a permanent install kit that was designed for applications where the tow vehicle has air brakes. What's great is this system is designed to interpret how hard you are applying the the tow vehicle brakes and put a proportional amount of braking on the tow vehicle brakes. We had the chance to install this kit on a similar 2012 Jeep Liberty too and shot an install video that you can use...
    view full answer...
  • Does the Reed Switch Eliminate the Brake Light Switch on an SMI Braking System
    According to the installation instructions for the SMI Air Force One Supplemental Braking System for Motor Homes with Air Brakes part # SM99243, the reed switch attached to the actuator will power the LED. The brake switch will no longer be providing the signal for the monitor light. Exercise caution when installing the reed switch. If the reed switch arcs to ground, it will either no longer work or cause the LED to stay illuminated at all times. You can reference the installation of the...
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  • Recommended Supplemental Braking System to Flat Tow a Subaru Forester
    The brake controller you mentioned is utilized when towing a trailer or a tow dolly, but when you flat tow a vehicle a different system is used that will utilize your motorhome lights but will also utilize the braking inside your towed vehicle. For your Subaru Forester, I recommend the Air Force One, part # SM99243. It's great for motorhomes with air brakes like your Winnebago because it only engages the Subaru's brakes when the air brakes are activated and not when the brake lights...
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  • How Installed SMI Air Force One Receives Power While 2016 GMC Canyon Being Towed
    The power and functionality requirements of the Air Force One System, Item # SM99243, are taken care of when it is directly attached to the vehicle battery during installation. Everything will still function even if the negative cable is off of the battery because only the positive terminal and a ground location are needed The Air Force One works by engaging the brakes for a towed vehicle when it receives air from the coach air connection. It diverts a matching amount of air through...
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  • Braking System that Doesnt Apply Toad Brakes with Exhaust Brake
    We have a supplemental braking system that is ideal for you situation. The Air Force One, part # SM99243, will do just that. The Air Force One only engages your toad's brakes when the air brakes of your motorhome are applied. And since they aren't being applied when you're using your exhaust brake the toad won't brake just from using the exhaust brake. I've linked a video of the Air Force One being installed in a new CR-V for you.
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  • Are Fittings Included with the SMI Air Force One to Install it on a 2008 Tiffin Motorhome
    The SMI Air Force One # SM99243 actually includes tees that allow you to tap into the air brake system on your 2008 Tiffin Motorhome. This kit comes with everything that you need to tap into and repair the lines that it uses. If you check out page 8 of the linked instructions and then jump down to page 11 you can see all of the specific instructions about installing this unit on your Spartan chassis.
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  • Can SMI Air Force One Supplemental Braking System be Used on 2015 Cadillac SRX
    We had the chance to install the SMI Air Force One supplemental braking system part # SM99243 on a 2016 Cadillac SRX and we had filmed the install. I attached a link to this page that shows the install for you to check out. This is designed to be used on motorhomes with air brakes and can also be used on air-over-hydraulic brakes with an additional 1/4" DOT air line (not included).
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