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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
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Retail:$1,830.10
Our Price: $1,329.00
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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. Lowest 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 etrailer.com or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (190)
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  • Why etrailer?

Demco Tow Bar Braking Systems - SM99243

  • Brake Systems
  • Proportional System
  • Air Brakes
  • 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.


Features:

  • 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


Specs:

  • 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 instructions

This Product Fits The Following Vehicles





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   (190 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.

by:

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.


Comments
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

by:
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 ground...it 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.


Comments
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

by:
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.


Comments
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

by:
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.



by:
Allegro

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.



by:

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.



by:
2016 GMC Canyon

Vehicle 2016 GMC Canyon Diesel.
Installation
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.



by:
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!!



by:

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



by:
2017 Jeep Wrangler

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


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

by:

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.



by:

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.



by:

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



by:

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.



by:

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!



by:
Jeep Wrangler

We tow the Wrangler behind our 36' Monaco. Easy setup, confident towing, and easy disconnect. Highly recommend.



by:
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.



by:

product shipped quickly, installed with video instructions and one phone call, 13000 miles behind motor home and everything works as it should. Great resource for DIY and saved thousands over professional installation, just follow the instructions and double check everything.



by:

Should have bought this system sooner. I love that it's fully proportional and truly "plug and play." So much easier to use than my old supplemental braking system that sat on the floor of the car and had to be installed/removed at every overnight stop. I installed it myself, which requires an intermediate level of mechanical aptitude. The instructions that came with the kit and DEMCO's tech support were extremely good.



by:

I LOVE THE NAME!! Works perfect and nobody even knows its there when I'm not towing the vehicle.



by:

We've had a good experience using the Air Force One braking system. Installation was easy and all you do is hook up an air line to the tow vehicle and off you go. No other adjustments needed so I like this unit.



by:
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.


Comments
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

by:

great product and Etrailer delivered quick and great customer service



by:

My Air Force One braking system arrived quickly and I installed it using the vidio on there site. It works great and I thank etrailer for there partnin my success.



by:
Jeep

Have had the Demco Air Force One on my towed Jeep for a year now, with many trips. Works perfectly, very glad I bought this. Simple to hook up, just hook up the one end of the air hose, since while traveling I leave the tow bar on and the hose hooked to the coach. Glad I didn't get one of those boxes that goes on the floor that has to be taken in and out each time.


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Ask the Experts about this Demco Tow Bar Braking Systems



  • 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...
    view full answer...
  • 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.
    view full answer...
    Image 1 for
  • 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...
    view full answer...
  • 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...
    view full answer...
  • 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...
    view full answer...
  • Air Force One Breakaway Not Working on my 2014 Honda CR-V
    When the breakaway switch will not activate the air cylinder to apply the brake pedal on the SMI Air Force One # SM99243, the first thing to check is the inline fuse at the towed vehicles battery. If it is blown it will have to be replaced. If the fuse is good the next thing to check is that the air lines and check valves are properly installed. If the airline in is routed to the out and the out is routed to the in, the system will work when attached to the coach but the breakaway system...
    view full answer...
  • Will SMI Air Force One Supplemental Braking System Work with 2015 Toyota 4Runner
    I spoke with my contact at SMI and he stated that the Air Force One Supplemental Braking System # SM99243 referenced in your question will work with all towed vehicles, including your 2015 Toyota 4Runner. This system has the necessary provisions and instructions for vacuum boosted brakes, active brakes and hydroboost brakes. My contact states that your 4Runner most likely has hydroboost of some sort, but to verify this, a simple test can be performed. With the key in the tow position,...
    view full answer...
  • Compatibility of Flat Towing 2014-2016 GMC Terrain and SMI Air Force One Braking System
    The GMC Terrain models from 2014 through 2016 can call be flat towed four wheels down, but it is recommended to have a speed restriction of 65 mph on all of these models when doing so. It is also recommended to start the vehicle and let it run for 5 minutes prior to towing and at each fuel stop. This gets the moving components properly lubricated to prevent damage. You will also want to let the engine idle for 3 minutes or more prior to driving after towing it. You will also want to...
    view full answer...
  • Can SMI Air Force One Brake Indicator Light Mount in Motorhome?
    I reached out to the manufacturer in regard to your questions about installing the SMI Air Force One Supplemental Braking System # SM99243 and was told that in regards to the indicator light, you can run 14 gauge wire the length of the coach though you will have to wire in a 4 post relay because the reed switch can only handle 100mA of current and will not be able to send the signal that distance; and that the 4 terminals on the relay will be 12v power-Ground-Signal from the reed switch...
    view full answer...
  • Is SMI Air Force One Supplemental Braking System Transferrable Between Cars?
    The SMI Air Force One Supplemental Braking System for Motor Homes with Air Brakes # SM99243 is not transferable between vehicles and once it gets installed it is there during normal driving but will not have any effect on your Tahoe whatsoever. As for how long it takes a normal person to install, that is not something I would be able to quantify; there are simply too many variables. Someone with a bit of mechanical know-how could do it, but there are some involved aspects, as you can see...
    view full answer...
  • Is a Third Check Valve Needed for the SMI Air Force One on a 2018 Ford Edge
    I saw the tech note that you were referring to about some of the newer Ford vehicles requiring a third check valve. However, your 2018 Ford Edge has a factory check valve on the brake booster lines so there is not a third one needed and you will have everything you need with the two that are included with the SMI Air Force One Supplemental Braking System part # SM99243. This is an excellent system that will work great for you so long as your motorhome has air brakes. I called my contact...
    view full answer...
  • 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.
    view full answer...
    Image 1 for
  • 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.
    view full answer...
  • 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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  • How Easy is it to Connect the SMI Air Force One Supplemental Braking System Once Installed
    Once the SMI Air Force One Supplemental Braking System # SM99243 is installed it is only a matter of making a couple of connections between the RV and the toad (lights, breakaway cable/braking system, tow bar, safety cables). So depending on all of the other parts you have in your flat towing set up and whatever procedures the toad has to go through to be flat towed (check owner's manual) it could be as little as 10 minutes; maybe more maybe less. I have linked a video showing an example...
    view full answer...
  • Installation of SMI Air Force One Supplemental Braking System and Ease of Disconnect
    The SMI Air Force One Supplemental Braking System # SM99243 referenced in your question is confirmed to fit your Suzuki Grand Vitara and is a great choice if your RV has air brakes. This is a true, proportional system, which means it will actually use air pressure from the RV's brakes to apply the brakes in your towed vehicle at the same time and with the same intensity. The initial installation can definitely be a bit more involved than some other systems, but a great thing about this...
    view full answer...
  • Is SMI Air Force One Supplemental Braking System Compatible With Air Over Hydraulic Brakes?
    Yes, the SMI Air Force One Supplemental Braking System # SM99243 is compatible with motorhomes that use air over hydraulic brakes like your 2003 Safari. It is possible that you will need to use another 1/4" DOT air line but it is going to be compatible. I've added links to a pair of videos on this system for you to take a look at as well.
    view full answer...
  • How to Make the Airline Connections on the SMI Supplemental Braking System Part # SM99243
    There are two airlines that must be spliced into on the coach which will then run to the air tank assembly included with the SMI Air Force One Supplemental Braking System part # SM99243. One of these lines is for supply-air and the other is for metered-air. The supply-air line is a 5/8" diameter hose (usually green but not always) which goes from the service relay valve to the braking air tank (see first photo). Once you find this line you will need to cut it in half and install the supplied...
    view full answer...
    Image 1 for Image 2 for
  • Does the Air Force One Brake System Come with Everything Needed for the Installation
    The SMI Air Force One Supplemental Braking System # SM99243 comes with everything you need for it to work with a motorhome that has air brakes. The only time that something else might be needed is if you have air-over-hydraulic brakes. In that case you may need additional 1/4" DOT air line. Attached is a review video and the installation instructions for you to check out. A complete flat towing setup includes a base plate kit, tow bar, safety cables, vehicle tow bar wiring, a supplemental...
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  • Does the Air Force One Activate the Towed Vehicles Brakes When the Exhaust Brake Is Used
    The Demco Air Force One Supplemental Braking System # SM99243 is actually the perfect solution for you since it does not engage the brakes on your toad when the brake lights on your coach are lit; it instead relies on the the coach's air brakes to be activated and will prevent false braking that occurs with other systems that react to the brake light signals. Because of this, when you use the exhaust brake instead of the coach's air brakes, it will not create a situation where the toad's...
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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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  • Is Air Force One Supplemental Braking System Compatible with Air over Hydraulic Motorhome Brakes
    Yes, the Air Force One part # SM99243 that you referenced is compatible with air over hydraulic brakes like what your 2003 Safari Cheetah has that is built on a Roadmaster M4R Series Chassis. I attached a review video for this system for you to check out as well.
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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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  • Air Force One Braking System on 2017 Grand Cherokee Activates While Backing When Towing Boat
    I'm assuming this is occurring when you are towing the boat, and not a situation where you are double towing the boat and the Grand Cherokee behind the motorhome (a practice that is not recommended). The Air Force One can't apply the brakes unless it's connected to the motorhome. It sounds like your boat trailer might have a surge or hydraulic coupler on it. When you back the boat, the coupler compresses, thus applying the brakes. Most surge couplers will have a manual or electric lockout...
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