Buying & Building a Medium Ambulance into an RV – The FAM-BULANCE

My wife had suggested several times that we look at buying a small motor home when I retired so we could do some traveling, and have limited living accommodations on the road. I grumbled that any RV that met my standards for durability wouldn't fit in the driveway, and would probably cost as much as our home. The RVs that I could financially justify had the physical ruggedness of a back yard tool shed with aluminum siding and coffee can lids for shingles. End result – no RV.

Months ago, my friend, MNtal, told me that he was thinking about buying a medium ambulance for conversion to an RV. I had never heard of a medium ambulance, so he explained the finer details to me. I mentioned what he was doing to my wife, and she said why don’t we do that (besides, it gave me a retirement project - one of many).

Moving ahead, MNtal bought an ambulance and transported it back to MN in only a few days in the absolute dead of winter. After he recovered from the trip, we talked some more about medium ambulances, and I started to do some research. I found that:

• Medium ambulances appear to be more common in the east than anywhere else in the country – nearly all the ads I saw were for ambulances located in the east.
• Various makes of trucks are used as the base for medium ambulances – Ford, Chevy, IH, Sterling, and Freightliner are the primary vehicles, though now Kenworth is also getting into the business.
• Because there are multiple trucks used, there are multiple engines to choose from – Mercedes, Caterpillar, Cummins, and IH. More people swear by the Cummins, followed by the IH.
• There are also multiple ambulance body manufacturers. They are all working from the same GSA Federal standard (KKK-A-1822E), but each has their own features and quirks. There are four primary brands out there: Medic-Master was built by American LaFrance, which is now bankrupt. Horton, Braun, and Road-Rescue build ambulance bodies, and all have their own advantages and drawbacks.
• Medium ambulances are manufactured as 8 ft and as 8 ½ ft width. The module (ambulance portion) is usually either 12 ft long or 14 ft long.
• Even with a Federal specification, external and internal layouts are largely as per the buyer’s wishes, so every ambulance you look at is slightly different than the last. Some of the various features include: extended cabs, auxiliary body air conditioning, diesel generators, built in refrigerators, multiple stretcher mounts, bariatric (large patient) capabilities, and combinations of whatever sirens, lights, and emergency equipment are as per every communities’ wishes. Cabinets and storage are also whatever the customer desires.
• If you purchase from an ambulance dealer, they are generally required to deactivate the emergency equipment – the red lights and siren. If you buy from a fire department or a private seller, it may come with the emergency equipment, but deactivating it may be required by your insurance company and your PD.
• You can buy a medium ambulance from a private party, a fire department/ambulance company, or from a dealer. You gets what you pays for. Dealers charge more, but they refurbish used ambulances so you can head home with a high likelihood of making it. Private party sales are probably the riskiest – you are leaving on a trip, driving a strange vehicle for the first time, whose repairs may not have been done by a qualified emergency vehicle mechanic. Any roadside troubles, and you may have a problem.
• Medium ambulances are built on a truck chassis, but there are many differences between a truck and an ambulance. For example, ambulances have battery disconnect switches, multiple batteries, strange plumbing for heaters and ACs, “high idle” (the engine idle speed increases to about 1500 RPM when the body is powered up, the transmission is in neutral, and the parking brake is on. This is so the 270 amp alternator and AC can deliver their full rated performance while the ambulance is parked and loading), and air suspension with an air dump feature (so you can load patients more easily). Believe me, there is a learning curve when you start to drive an ambulance (even a retired ambulance).
• If you do buy an ambulance, get all the documentation that you possibly can. Not just whatever is needed to license it, but as much data on the ambulance portion (the module) as possible. If you’re lucky, you will be able to get the official manufacturer’s manual on your vehicle included with your purchase.
• After the Ghostbusters movies came out, old Packard and Cadillac ambulances became an instant collectible, and they are still priced outta sight.
• The Bible for existing ambulances is KKK-A-1822E. This GSA Federal standard specifies the precise details that every type of ambulance must meet. Virtually every ambulance (except possibly an old Cadillac or Packard hearse-ambulance) has the same equipment (warning lights, inverters, oxygen gear, heaters, ACs, etc). You can easily track down a free copy through Google.
• KKK-A-1822E is being replaced by NFPA 1917. Unfortunately, NFPA 1917 is not available unless you buy a copy from the NFPA.

My plan was to build an ambulance into a legal RV. Here in MN, that requires:

Subd. 17.Motor home.(a) "Motor home" means a recreational vehicle designed to provide temporary living quarters. The motor home has a living unit built into as an integral part of, or permanently attached to the chassis of, a motor vehicle or van.

(b) A motor home must contain permanently installed, independent, life-support systems that meet the American National Standards Institute standard number A119.2 for recreational vehicles and provide at least four of the following facilities, two of which must be from the systems listed in clauses (1), (5), and (6): (1) a cooking facility with liquid propane gas supply, (2) a refrigerator, (3) a self-contained toilet or a toilet connected to a plumbing system with a connection for external water disposal, (4) a heating or air conditioning system separate from the motor vehicle engine, (5) a potable water supply system including a sink with a faucet either self-contained or with connections for an external source, and (6) a separate 110-125 volts electrical power supply.

(c) For purposes of this subdivision, "permanently installed" means built into or attached as an integral part of a chassis or van, and designed not to be removed except for repair or replacement. A system that is readily removable or held in place by clamps or tie-downs is not permanently installed.

(d) Motor homes include a:

(1) type A motor home, which is a raw chassis upon which is built a driver's compartment and an entire body that provides temporary living quarters as described in paragraph (b);

(2) type B motor home, which is a van that conforms to the description in paragraph (b) and has been completed or altered by a final-stage manufacturer; and

(3) type C motor home, which is an incomplete vehicle upon which is permanently attached a body designed to provide temporary living quarters as described in paragraph (b).

(e) A motor vehicle with a slip-in camper or other removable equipment that is mounted into or on a motor vehicle is not a motor home, is not a recreational vehicle, and must not be registered as a recreational vehicle under section 168.013

With these thoughts in mind, I started checking the web sites, and following leads. Ambulance Trader ( and Fenton Fire ( have many listings (all of which are at least one time zone away from me). I finally settled on a 1999 Freightliner / Medic-Master that was available from a PA dealer. Several e-mails and phone calls later, I flew to Philadelphia to see what they had. The on-line video of the Medic-Master had me 90% convinced, but there was no way that I’d cough up that much green stuff unless I saw it up close, and had a chance to drive it. Good old Hertz set me up with a car that was about the size of my shoe, and I managed to get to the dealer despite my Garmin trying to take me on a sight-seeing tour of the eastern seaboard.



I was impressed. It looked great, and sounded even better. My sources who drove emergency vehicles had told me that the ONLY engine I wanted was the Cummins 5.9, which meant a Freightliner. Medic-Master and Horton also have slightly more headroom than some of the other builders, but their 72” clearance still meant that I had to stoop a little (but at my age, stooping a little is easier than it used to be). The vehicle had 5 exterior compartments, and 18 interior compartments of every size and possible location. A little tape measure work showed me that the exterior compartments would nicely hold an RV generator plus a decent sized fuel tank, and there was an interior compartment that looked perfect for a 2.7 CF refrigerator (the dealer confirmed that that same location was often used for refrigerators – obviously, great minds think alike.) The vehicle only had 51,000 miles on the clock, and also had a Cummins 5.9 diesel, an Allison 6-speed transmission, air ride seats, air suspension, and nice large air horns. What more could anyone want?

We took it for a drive through the area, and I was hooked. I decided that this unit was the one that had been calling to me from 1200 miles away. We cut a deal, and the vehicle was mine, with delivery as soon as it went through the shop for some refurbishing, including some new tires, paint, un-emergency-fying(?), fluids change, and all the rest. I had planned to ship it to MN for about $1600, but my son suddenly decided that we needed a road trip to “bond”. He’s 32 years old, but I guess bonding happens when it happens. I ran the math, and I figure that a “bonding” trip would cost me more than shipping, but it is what it is. The other thought is that after driving it home, I would have a pretty good idea of any problems I would have to deal with.

Tune in tomorrow---
In preparation for the trip, I decided to retire the existing Freightliner AM/FM/cassette radio and I bought a new AM/FM/CD/XM Panasonic radio, also from Freightliner. Their magic book told me that it would fit, and it came with the adapter cables for a seamless plug-&-play installation. I also decided to install new speakers since the existing speakers dated to 1999, and they were probably getting a little crispy. Because I'm a firm believer in Murphy's Law, I also bought a set of emergency triangles and an auto club membership (that will cover ANY vehicle I own…). My suitcase will be very close to 50 Lbs for the Philadelphia flight.

I spoke with the MN DOT about licensing it as an RV. They told me that if I had good documentation, licensing as an RV would be straightforward. Their advice boiled down to: Save every receipt so you can show what you did, and take photos of before and after.

My plan was to fly in on a Friday to pick it up, then stay near the Philadelphia airport until Saturday when son could fly in. We would then launch forth and head back to MN, stopping only for diesel, food, motels, and weigh stations (once it is licensed as an RV, we'll only have to stop at stations that require “All vehicles exceeding X pounds must stop” since the vehicle will not be a commercial vehicle or a truck anymore.

The trip back to MN should be “interesting”. I have restored several military trucks in the past, and I like driving with large mirrors, but the notion of bouncing along for 1200 miles is a bit intimidating (even with air ride seats). Once I get it back in my shop, the 1999 seats will be replaced with top of the line truck seats, so I just have to survive the trip. When MNtal drove his ambulance back from NY, he commented that the seats were totally and completely worn out, and about as comfortable as sitting on a pile of rocks, and I'm concerned that my seats are just as wonderful. We'll see.

When I picked it up on Friday, I was a little intimidated – I'd driven many trucks over the years, including some very large and ugly military vehicles (including armor), and even a few military ambulances, but never a creature like this. When I had found that Philadelphia was in the throes of repairing Highway 95, I decided to stay near the dealer for Friday night, and then drive to the Philadelphia airport on Saturday when traffic would hopefully be a little better. In the mean time, the local Wally-World provided bottled water, a cooler, ice, snax, and all the rest that would be needed for our journey.

I found out another reason why son wanted to bond – he wanted to bring “some” railroad air brake parts (and 2 bicycles) back with him that he had bought from a scrapper in VA. According to the scrapper's scale, we departed his facility 870 Lbs heavier.

The trip back was mostly uneventful. The truck cruised all day at 65-70 MPH and had plenty of poop for hills – coming back, we crossed the Alleghenies, including one stretch on I-64 crossing Sandstone Mountain with four miles of 7+% grade. We crested that “hill” at 61 MPH, so the Cummins passed its first test with flying colors.

Driving through Indiana, we saw a tour bus suddenly pull off the road, and we immediately found out why. Someone hauling a load of very large scrap steel had lost part of the load, and the freeway was full of rolling, bouncing, tire-destroying chunks of whatever. While the cars around us dodged as well as they could, we heard a massive clunk from somewhere underneath. The truck sounded a little louder, so after a few miles, we pulled off at a rest stop to see what was going on. We found that the entire exhaust system was now junk – the muffler had a dent in the end like it had been slugged by a very large sledge hammer, and the exhaust pipe had been ripped in half at a rusty area. Thankfully, the break at the rusted spot saved the turbo from any damage.



We didn't have much in the way of tools with us, but using a combination of a Swiss-Army knife and a utility knife, my son was able to slither under the truck and cut the rubber suspension straps. We dragged the entire exhaust out and stuffed it into the back of the ambulance. When we left, we found out that an ambulance with straight pipes was a whole lot louder than we ever imagined. It was worse starting out from a stop, but when we were at freeway speeds, the noise wasn't too bad.

When we got back home late at night, we drove as quietly as an ambulance with straight pipes could drive so my neighbors wouldn't get up in arms. The next day, I drove to the nearby Freightliner dealer for some exhaust work. After spending more than $ 1000 on parts and labor, the truck is quieter than it ever was. The best news is that I had a lot of confidence in the vehicle – 1400 miles of no problems proved that the vehicle was sound.
Next was overhauling some of the compartment locks – the ambulance had spent its entire life tucked away in a fire station, and the compartments had probably never been locked. Some I was able to clean and get working, but some were so corroded that I gave up and just bought new cores for them from an ambulance parts dealer.



Now that it is back home, I can do some serious measuring and serious planning before I do some serious installing. The refrigerator will be first since I know exactly where it has to go. Next will be the sink and the cooktop - after some thought, the key location is the ambulance's work counter and CPR seat area. I'm going to remove the CPR seat, and install a Corian or Avonite counter top over the entire 6 ft length. The cook top will be installed in the old CPR area since it is an open location that I can add an exhaust hood to with minimal headaches, and the sink will be installed nearby.

The cooktop also needs a propane supply. A 20 Lb BBQ tank would run the cooktop for at least one season, but the generator I'm also planning to install will be propane fueled, so a larger tank might be smart. I lucked out with this particular ambulance – it has a pull-out oxygen bottle rack that's designed for large medical oxygen bottles. I stood on the rack to see how solid it was, and it didn't wiggle one bit, so it will become the basis for a propane rack for either a 60 Lb or a 100 Lb bottle.

Electrically, an ambulance can be loads of fun… Mine has four batteries, a 270 amp alternator, and an automatic load startup and load shedding feature to reduce the battery surge when the module (ambulance portion) is powered up, and then to also shed loads if the battery voltage starts to drop. All the selector switches in both the front console and the module console only activate relays, with some time delay features and interlocks added for entertainment. Thankfully, ambulance manufacturers are very careful about color coding and wire labeling, so you at least have a starting point.



Any time you start to work on something as challenging as ambulance wiring, you learn to have a camera, pad of paper, and a flashlight nearby.

There are two FLUORESCENT LIGHT switches near the side door and the rear door that turn the fluorescent lights on for 10 minutes – the delay relay is controlled by a separate resistor – after I replaced the 880,000 ohm resistor with a 440,000 ohm resistor, the delay dropped to 5 minutes.

I'm chasing the reason why the left side ceiling lights are always on when the module is powered up. It may be deliberate, or it may be a defective switch. Some voltmeter work should show the answer.


Note the brown burned area on the one yellow slide-on terminal - the terminal is on the suspect switch.
Write up looks real good, I'm trying to decide if the Electrical control panel looks more intimidating in pictures or in person. :Wow1:


"Jackaroo of all trades"
Welcome to the ambulance club! The electrical is always fun, I cut mine out and start from scratch. They are tough trucks, I have scraped all the lights off one side on of my Road Rescue in the woods of Tennessee, but the metal was completely unharmed. (nothing paint didn't cover up) Very durable bodies, and the commercial truck platform is certainly the way to go. Good luck, can't wait to see the build up!
Starting about 2000 or so, ambulances started to go with digital everything. The good news is that panels are simplified, the bad news is that parts are only available from the manufacturer. My ambulance is a Medic Master, which was made by American LaFrance, who went bankrupt. Thankfully, mine is a 1999, and it uses Carlingswitch switches, Bosch relays, and similar parts available from NAPA. I would be in a possible mess if I had a 2005 or so that was all digital and the manufacturer just went bankrupt. My wiring is a bit bulkier, but I can repair it with a test light and a voltmeter. I agree with removing everything and starting over if you don't need the capabilities of an ambulance - even if you want some flashing lights, you can simplify things a whole lot if you don't have to comply with the GSA ambulance requirements. Myself, I like the challenge of figuring it all out. Thankfully, the manufacturers were very careful to label wiring very carefully, so it is easier than it could be.

I was asked by a friend why I bought an ambulance from a bankrupt maker. Simple - since it uses conventional components from normal ambulance suppliers, I can track down anything I need, and I'm sure that buying a Bosch relay from NAPA can't help but be cheaper than buying it from Medic Master. Medic Master was built by American LaFrance, who built fire equipment for nearly 200 years, and I kinda like the 200 years of history that's there. Take a look at an American LaFrance chrome plated vehicle badge sometime - they're beautiful. My logo for the Fam-Bulance will include some of the LaFrance design.


The panel can be intimidating, but mostly what you see are the load demand sequencing panels. They were made by Wired-Rite Systems. I'll e mail them in a week or so for the details on how to set them up - that plus looking at the LED pilot lights when I turn something on/off will show me what's what. If you want to replace your present system with a digital system, RCTronics ( makes nearly off-the-shelf digital packages
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"Jackaroo of all trades"
I figured it was a good idea to design my own panel so when if it breaks, I have a pretty good idea what's wrong.

Sent from my SGH-T889 using Tapatalk
Amen! When you have to figure out someone else's system, lottsa luck. I learned from a very skilled ambulance electrician that the wiring systems and methods are pretty common throughout the industry and that an electrician can handle a different brand than he's used to fairly quickly, but I haven't found an AMBULANCE WIRING FOR DUMMYS book yet (I'm still looking, though). There is a scan of a Horton manual from the late 1980's on the internet, and that has been a help.

Generally, I open the module panel, sit on the attendant's chair, and see what pilot lights come on / go out when I flip switches. The whole process should keep me entertained for years...
I've been asked where my ambulance came from - it was Global Emergency Vehicles, in Levittown, PA. They sell new and refurbished ambulances, and have a huge inventory to work from. Their refurbished ambulances are inspected, repaired, and serviced as needed to bring them up to ambulance standards, so I felt confident that I could make it home. Their sales rep, Shawn McCusker, told me that about 10-15% of their sales are to non-ambulance users, such as surveyors, service trucks, and similar. I probably paid a bit more than buying from a fire department sale, but I also got an inspected, serviced, and ready to roll vehicle.
My plans also include a rooftop RV air conditioner. Since my garage door is 9'-11”, and the truck stands 9'-6” right now (with the suspension dumped), the 8” height of a Coleman Mach-8 will probably cause problems. That will move the installation of a roof top AC to next spring, when I'll also be able to enlarge the garage door a bit. One option would be to see if HoseLine (the manufacturer of my while-driving ambulance air conditioner) could provide a 120 VAC add-on AC for the module. The cost of the HoseLine might be less than enlarging the doorway and replacing the door, plus buying a roof-top AC unit.

At the same time, I'm also replacing the module's present 120 VAC, 15 amp standby / battery charger power inlet with a 120 VAC, 30 amp marine power inlet. I'll also install a 30 amp receptacle in my garage. Thankfully, ambulances have plenty of access panels that can be removed to get at wiring.

Back to 12 volts-

Even though there is a truck cab disconnect switch, it only shuts down battery power to the truck. You can never assume that a circuit is dead until your meter confirms that it is off. When I pulled out the battery box for the first time, this really became apparent: there are probably half a dozen separate taps (with in-line fuses) to the four paralleled batteries for radios and other things that you want to be able to use regardless if the truck or module are “on”. Figuring out which does what is straightforward – just remove a fuse, and see what doesn't work any longer. Ambulances have fuses on virtually every circuit – if something doesn't work, look for a hidden fuse before you panic.



This becomes critical when you decide to tunnel into the cab console to see what you have to work with. Never assume anything is dead until your meter or test light say it's dead, and even then be careful because you might bump something nearby that isn't dead – you might want to be very careful with the way you move tools around in there…. Many cables, such as radio interconnect cables, are left at full length since their connectors are often molded to the cable, so you might have an extra 20 ft of cable. Virtually every cable or wire in an ambulance is run in convoluted tubing for physical protection, so an extra 20 ft of radio cable can get very bulky very fast. Since the radios had been removed from my ambulance, and I didn't plan on installing any municipal-type 2-way radios, I felt safe in removing the radio cables, but I had a neighbor sit in the module and pull on what I figured was the same cable before I cut it – just in case. When I removed the leftover radio wiring, I wound up with a 5 gallon bucket stuffed full of wire, and another bucket full of convoluted tubing – I saved the tubing, and gave the wire to my electrician neighbor for his scrap bin.

There are components installed that I know I will never use, such as an IV bag heater or the suction pump. The IV bag heater can't be adjusted for pizzas (98-100 F is full speed), so it will wind up on E-Bay. The suction pump will probably also meet the same fate. The IV heater is installed in an interior cabinet that looks perfect for keeping all the paperwork, manuals, and misc. that will result from this project.


Well, I finally found out why the module left side dome lights were on when the module was powered up -- they are supposed to come on that way when the side door is open. I'd never closed the side door when I was chasing circuits. As soon as we closed the door, the lights went off. We also found the relay in the panel for the lights as well. As Stan Laurel once said to Oliver Hardy "Gosh, I'm dumb today..."

More and more, I'm learning the systems that I have to work with - and I'm impressed.
MNtal stopped by last night, and we waved our arms in the air for hours discussing the optimal layout for an ambulance-to-RV project. He likes to build rock crawlers from scratch, while I used to restore military vehicles for an Army Reserve museum - as a result, we both see projects a little differently. MNtal plans to strip his module, and totally rebuild it, while I'm going for a several step process:

1. Get it to the point that it can be licensed as an RV
2. Get it to the point that it can be used for a day camper (use a Holiday Inn at night)
3. Get it to the point that it can be used for several days as a stand alone camper

I'm planning to keep as much of the original interior as possible - no way do I want to do away with 18 storage compartments!

That being said, there are some decisions that are simpler than others, such as what to do with a small, floor level, sliding-door cabinet (it will become a drawer), or what to do with a space that looks like it may have had a microwave in the past (install another microwave). The squad seat will wind up being reworked into some sort of a combination sofa-bed. The existing rear bumper is designed for an ambulance, and sticks out 16" from the body, complete with rubber dock bumpers. In order to better fit it into my garage, the bumper will be rebuilt with some box tube, and will wind up with a Class-4 hitch while I'm at it. The end result will probably only extend about 8" from the module.

I've also been looking at new cab seats. I can get them through Freightliner or some other dealer, or look for RV cab seats. The problem with RV cab seats is that the ambulance is a walk-through, which means that you can walk (stooped over) between the cab and the module. The wider the cab seats, the harder this becomes. The leg room is also limited in the cab - I had thought about an extended cab ambulance, but the extended cab models I found had other problems -- no walk through, the wrong engine, too old, and usually too much money - plus, an extended cab version wouldn't fit into my garage. As a result, I'll probably wind up with top of the line truck cab seats for the cab.


Expedition Leader
The squad seat will wind up being reworked into some sort of a combination sofa-bed.
We have had success with using the jack knife sofa's from these guys. They make them in a range of lengths and it is fairly easy to cut up the base they provide to fit over the wheel well of the Ambo. The only issue I had with the latest one is that it is about 6" higher than I would of liked due to the outside drawer which we wanted to keep for all the outside cooking gear.

The existing rear bumper is designed for an ambulance, and sticks out 16" from the body, complete with rubber dock bumpers. In order to better fit it into my garage, the bumper will be rebuilt with some box tube, and will wind up with a Class-4 hitch while I'm at it. The end result will probably only extend about 8" from the module.
I know your pain with this one. Luckily I have 1 1/2 acres to park in but I will be watching your progress with the bumper. I need to get a bit closer to the back for mounting the motorcycle lift. Every inch of leverage counts.