How to Build a Real Overland Expedition Truck Camper

Expert Advice from Overlanding Legend Gary Wescott

Few couples are more recognizable in the overland community than Gary and Monika Wescott. In fact, you can even say they’re living legends. For more than 48 years, the couple has explored the world from the deepest jungles of the Amazon to the frozen steppes of Siberia. Their travel and adventure stories have been published in 15 countries and 10 languages around the world. While the backpack remains an important item in their travels, most of their adventures have taken part in a specially-built Ford overland expedition rig called the Turtle V. As you’d expect, Gary and Monika have extensive life experience when it comes to building the ideal truck camper rig. In this interview, Gary Wescott explains in detail how to build a real overland expedition truck camper rig using a Ford F550 with the legendary 7.3L turbo diesel.

Thanks, Gary, for taking the time out of your very busy schedule to talk with us. Where are you now and what are your plans for the rest of the year?

Gary: We just returned from a six-week trip in Baja California, doing a little shakedown run with The Turtle V. It hadn’t really been on the road for a couple of years and we also had some stories we were researching.

Let’s talk about your rig, The Turtle V. How long have you owned it and why did you chose to use a Ford F-550 with the 7.3L Power Stroke turbo diesel as the platform?

Gary: The Turtle V is the fifth of a series of expedition trucks we’ve built and used over the 48 years. At the time we chose the Ford because it had clearly the best engine and Ford had become a sponsor. F-series have been the best-selling truck in America for 40 years. I love the bumper sticker in Montana: “Eat more lamb. Twenty million coyotes couldn’t be wrong.” We also chose the Ford F-550 because it had the weight capacity to allow us to build a hard-side camper and not pull a trailer anymore. The 7.3L Power Stroke turbo diesel was clearly one of the best engines that Navistar had ever built for Ford.

We agree. It’s a great engine. Do you have any advice for those who are building their own expedition truck camper?

Gary: People quite often ask what I would suggest if they wanted to build a truck like ours, a real overland expedition camper truck. My advice has been the same. Don’t buy a new truck. Look around and find an old one, specifically one that will run on any kind of diesel anywhere in the world and carry the load you are anticipating. Adding overload springs and more shocks to an F-150 does not change the engineering that went into its frame, brakes and transmission. I can certainly recommend personally the F-550 with its 17,500-pound weight capacity or the even the Dodge 5500 which is a comparable vehicle. You need to pick an engine that can be worked on in foreign countries and one that will run on regular road diesel, any kind that comes out of the pump. A manual transmission is by far the best choice!

With so many things to consider when building a rig, what should be the first step?

Gary: First you need to decide where you’re going and for how long. Will you be visiting national parks, taking weekend trips to the beaches of Mexico, or driving around the world? If the former, do you really need four-wheel drive, a winch, and locking differentials? Is it going to be warm and sunny where you’re going? Your personal level of comfort is critical. Can you really stand sleeping in a rooftop tent for two weeks in 85 degrees F and pounding rain in the middle of Brazil? The second consideration is whom you are traveling with. Will it be just yourself and a companion, or with two kids, a cat and a dog? These factors will influence both camper size and equipment needed. Once again, where are you going, with whom, and how comfortable do you want to be? The catch is, if you go too big or too heavy, or you are over loaded, you won’t be able to get to the places you want to go.

What mods did you make to your truck to make it more trail worthy?

Gary: The basic F-550 pickup is a pretty stout vehicle, and by virtue of the fact that it is a pickup truck, it was not designed as a delivery vehicle around town. Heavy-duty pickup trucks are designed for serious work. That’s an advantage when it comes to reliability and their ability to carry a load and hopefully not break. We tried to keep the F-550 as factory stock as possible, which could make it easier to get parts on the road if we needed them. There are some modifications we have made that are covered in a nine-part blog found on our website. We have a custom suspension system by Deaver and Hellwig. We changed the turbo to an ATS. Dynatrac Spin-Free Hubs were a must. A South Bend Clutch became obvious. After-market products like K&N Air Filters, Amsoil oil filters, a coolant filter and other important modifications continue to make the vehicle and camper more reliable. A custom bumper by Buckstop was a major improvement as well.

As I have said many times, the advantage of owning an American pickup truck is that there are millions of them out there. What that means is, there are thousands of companies making products just a little better and a little stronger than what Detroit could afford to use on an assembly line vehicle. Better bearings, better brakes, better water pumps, better air filters, better turbos, better U-joints—you name it. Some company is making something better to replace something that might break on the road of adventure when you are thousands of miles from home or the nearest dealership.  Take the money you save from buying a new vehicle and use it for aftermarket parts to make it better and stronger.

Can you tell us about the Tortuga Expedition Camper? Who built it and how was it built?

Gary: The Tortuga Expedition Camper was designed and built by us. We saw what the Europeans were using for their expedition vehicles and gained from many of their ideas. Our goal was to build a camper as big on the inside as possible and as small on the outside as possible. After some 35 years of traveling back roads around the world we pretty much knew where we wanted to go and what kind of a vehicle could go there. The camper was built to be comfortable for two people instead of being uncomfortable for four. By looking at our nine-part blog series folks can see that we created an exoskeleton of welded aluminum and then fitted panels of fiberglass-covered Nida Core into that frame. They were attached with Sika Flex marine adhesive. After that, it was just a matter of fitting the components, mostly using a tape measure and paper and pencil, to see whether the refrigerator, the water tank, the batteries, the bed, the sink, and all the other components would fit. At that time we did not have a CAD program. It would’ve been a real advantage. When you design a vehicle like this using CAD and you move the sink it tells the bed and the refrigerator and if they don’t fit a red flag comes up.

One of the most critical elements of the design was the mounting system of the camper on the frame of the F-550. You cannot twist a box. It will break. Most American and European expedition campers use some kind of a three-point mounting system. We designed our own with the help of the engineers at Midwest Four-Wheel-Drive, (Big Foot), and it has proven reliable. Just remember, you can’t twist a box.

It appears that European trucks and campers have influenced your decisions. Can you explain to us how?

Gary: When we returned from our Trans-Siberian expedition across all of Siberia in the wintertime, with temperatures below -86 degrees F, and later traveling around parts of Europe, we attended African Safari events and other overland vehicle exhibitions. We saw many ideas that we could incorporated into our Tortuga Expedition Camper. We also learned more by visiting factories in Germany like Unicat, Alu Star and Langer and Bock. Those companies have been designing and building expedition campers for decades. There were important concepts like using every single square centimeter. Cupboards and shelves were built to fit exactly what we knew what was going to be stored in them. In order to make the camper as big on the inside as possible, our bed collapses into a single couch during the day and folds out into a full bed at night with the fitted sheets already on it. This greatly increases the living space. Perhaps one of the most interesting ideas the Germans came up with was, where do you put a bathroom and a shower in a small camper? We specifically did not want the classic American-style shit-shower-shave-cook-breakfast-all-at-the-same-time-please-don’t-get-the-toilet-paper-wet camper. Angling the sides of the roof was a Russian idea. It gives better clearance, and besides, in a camper you don’t stand up next to the wall. Eliminating a bed over the cab made it look less like a motorhome and the outside roof rack is extremely useful for carrying extra Jerry cans, firewood, and a storage box for travel equipment.

Do you really need that little sink with a special room to brush your teeth when you can reach the kitchen sink without moving your feet, or can you just brush your teeth in the kitchen? The Germans with their Spartan ideas figured this out. Put the shower in the doorway. It’s a space that’s always there. And have a Porta Potti, which does not require its own little room, slide out on tracks into the doorway. It is a simple use of space. Privacy you ask? If you are traveling in a small camper for a year and cannot go to the bathroom in front of your partner, you may have a bigger problem. Don’t forget to include a bathing option: A solar bag on the roof, sponge baths, a dive in the ocean with sea-soap or Joy detergent, or a real hot shower inside or outside your camper. Be aware that you need to plan on how you will handle personal hygiene before you stink.

That reminds me of another interesting modification. Hot water is a real luxury. Sure you can boil it on the stove for washing dishes or your face. We discovered two items that make hot water practical. The Eberspaecher D5 hydronic is a coolant heater. It is connected to the cooling system of the engine. It has its own little pump that burns fuel from the main diesel tank and heats water 160 degrees F.  Depending on where you set the valves at, its little internal pump will transfer that hot coolant to whatever you want to heat, including the camper, the engine or, have it pump that hot coolant through a flat-plate heat exchanger and you can have hot running water in the kitchen, in the shower and even the outside shower in about three minutes. A temperature control device keeps the water temperature down to about 120 degrees F so you don’t burn yourself. And speaking of heat, the compact diesel-powered Eberspaecher Airtronic is our primary heat source in the camper. In addition, while we’re driving in cold weather, the hot coolant from the engine is also circulated through a small radiator in the camper to keep things toasty on the road.

How much did you save doing everything yourself rather than going with a company that specializes in such builds?

Gary: Actually, we didn’t do it all ourselves. We hired individual experts for plumbing and wiring and other special technical jobs. Most of them had never built or traveled in an expedition camper before so they did not look through a filter that someone who has designed and built 20 or 30 looks through, backed by an engineering team! Expensive mistakes were made. Quite honestly, when I look back, it might’ve been a toss-up to just having somebody like Global Expedition Vehicles or Unicat build the camper to our specifications. That said, we would’ve missed all the excitement and the sweat and the frustration of building our own. Fixing the mistakes as we went along was time consuming. The truth is, designing your own camper is a can of worms and can be very frustrating. We know!! We’ve built, modified and traveled in five Turtles and two project camping vehicles built for Ford and Dodge. There are lots of mistakes to make. Unless you have the luxury of time and money to experiment as we have had for the past 40-plus years, there are some things to think about.

How large are the holding tanks in your camper and how many do you have?

Gary: We basically have five. There is a 12-gallon gray water tank in the back that holds the water from the sink where we wash dishes and brush our teeth. Our Thetford Porta Potti has a 3.6-gallon tank, enough for two weeks if you don’t fill it with water and pee. (Yes, overland travelers often use a pee jar at night.) We have another 12-gallon tank underneath the entryway which holds the gray water from our shower. That’s enough for about six nice hot showers. We also have a 14-gallon oil reservoir behind the right rear fender well of the camper because you cannot get the kind of oil you need to keep your engine alive in Third World countries. I once changed my oil in Kirgizstan and ended up trying to find a place to recycle the used oil. Finally I found a small shop and the owner told me in Kirgiz, “$5.00”. Oh wait! He wanted to buy the used oil! I gave it to him with an Amsoil hat.

Finally, we have a 40-gallon main water tank and two 5-gallon reserve cans on the back. Drinking water is very critical when traveling through other countries, not only because of bacteria and but also viruses. We have used the Everpure dual-filter system for many years. We super chlorinate the water just like most big cities do. We can fill from any source, lake, river, irrigation ditch, creek, gas station. We have two faucets. One for washing dishes and hands. The water has been super chlorinated so it has no bacteria or viruses. It just tastes a little bit like Los Angeles tap water. The second faucet has the Everpure dual-filtration in-line. The coarse filter protects the primary filter from dirt. The primary filter takes out big stuff like giardia and amoebas, and it also takes out bad tastes including chlorine which has already killed any viruses. It’s the best system for a compact expedition camper.

Can you tell us about the Turtle V’s electrical system?

Gary: Again, taking some ideas from the Germans, we use four deep cycle Odyssey batteries and two more of the same exact batteries in the engine compartment. We ordered the truck with the dual alternator system or the ambulance package as it is called. The primary 135-amp alternator charges the truck engine batteries for starting. The second alternator, modified to 200 amps, charges through a remote Balmar regulator and keeps the batteries in the camper charged [ed. note: check out a recent article we published on how to build one of these for your rig]. We also have two BP 85 solar panels on the roof so if there is sun, they keep things topped up. The reason we have the same size Odyssey batteries in the camper and the engine is first, Odyssey only makes one battery that does everything, deep cycle, marine and starting. Secondly, if one of the engine batteries should die we can just take one out of the camper and pop it in. It’s also a fairly common size battery, group-34. You can find it in most automotive shops in any big city. You don’t need to go to Camping World and use a forklift to get out your lithium or monster Lifeline battery replaced.

Did you need to make any modifications to your Ford F-550’s suspension to carry your camper?

Gary: Oh yes, we did make some modifications to this truck’s suspension. The multi-leaf spring packs by Deaver are designed to carry a fully-loaded truck, 14,000 pounds, all the time. Instead of three leaves and an overload spring we have 15 much thinner leaves. They flex and still carry the weight. We use dual Rancho RS9000 XL nine-position adjustable shocks on the front and two big RS9000 XL nine-position adjustable shocks on the rear. Hellwig air springs in the back gives the rear a little softer ride and Hellwig HD sway bars front and rear add stability in the corners. The front Rancho dual shocks are set on #3 and the rear singles on #6. Dual shocks in a lighter setting protect them from overheating. Shock absorbers will produce heat on a washboard road at 35 mph and that’s what destroys them. The Ranchos have been ultimately reliable for thousands of miles

After it is all said and done, do you have any regrets in any of your choices? Anything that you wished that you had done differently?

Gary: Any regrets? Actually we’re quite surprised, as we had never designed a hard-side camper before. Virtually everything that we have added or changed over the past few years, using this camper and modifying it as our knowledge increased about better products available has improved its function. We wouldn’t really change anything. I mean there are a few little engineering things like making the water pump easier to get to, but as I have written, if we are talking about the ultimate overland expedition vehicle, we need to be clear about the word ultimate. According to Merriam-Webster it means something that cannot be further improved or refined. Let’s keep that in mind. The Turtle V has been the perfect camper for what we needed for two people traveling in the third world countries around the world. That is exactly what it’s done and that’s what it was built for.

Have you suffered any breakdowns or other emergencies while exploring overseas? What tips do you have for those preparing for such contingencies?

Gary: Even as carefully designed and built as The Turtle V has been, things have broken. We cracked the frame down in Mexico and had to have it welded up with a patch. The support brackets on our camper broke because they were poorly engineered, but it wasn’t catastrophic. We’ve had some bolts come loose on suspension parts in the rear, a result of the absolutely horrible roads going across the Stans and Mongolia. Short story is, we have never been stopped on the road with something that couldn’t be fixed or patched on the spot. If there is a tip, build it very carefully before you leave and drive sanely, knowing that you are thousands of miles from help or the next dealership. A 14,000-pound expedition truck needs to be driven differently than a 3,000-pound Jeep. You are not in the Dakar race with a pit crew waiting for you at the next check point.

That’s great advice. What has been the biggest challenges full-timing and exploring in your truck camper overseas?

Gary: It’s mostly about your mental attitude. The first thing you have to realize is that everyone’s heart beats the same. We’re all human beings. If you treat people with respect they will treat you back the same. We have never ever had a really serious problem in I don’t know how many countries we’ve travel through, maybe 85. There are always the occasional drunks or man-boys but you can find them anywhere. I suppose one of the biggest challenges we continue to have in full-time traveling is keeping our fitness and health, which means some kind of exercise almost every day and doing our own cooking most of the time.

When you showed us your rig at the Overland Expo West we were impressed with the amount of storage and how everything in your camper is organized. Do you have any tips for our readers on how to stay organized?

Gary: One of the keys to enjoyable travel in a small camper is a rule that we’ve had from the very beginning. Everything has to have a place and if you move it, you need to put it back in its place. For simple organization in terms of spare parts and other commodities like sundries or even clothing for a long trip like we are about to take in South America, every item in every major storage compartment is in the computer, so if I need to know where some extra coffee filters are, I simply go into my master packing list and type in “find” “coffee” and immediately MS Word highlights exactly where those are. The key is, if you move those coffee filters, change the list in the computer or you’ll never find them again.

Your acrylic Seitz windows looks terrific even after years of travel. How do you keep them looking so good?

Gary: If we are going through trees or brush or mesquite we cover the windows with XPEL TracTape. On really bad back road trips like the Devil’s Highway along the Arizona/Mexico border we covered the sides of the truck with 3M Removeable Paint Protection Film. We also use Meguiars, Mother’s and Turtle Wax plastic polishes.

What kind of mileage are you getting with your setup?

Gary: What kind of mileage we get is a common question and honestly there’s no free ride. Back in the days of our Land Rover we got 12 or 16 mpg fully loaded. As we moved up through various different trucks and engines we got 12 to 16 mpg and now we get about 12 to 14 mpg depending on the wind and how fast we’re going. It’s better if we are on some two-track idling along at thousand RPM, just letting the engine torque move us down the road. I appreciate some of the newer vehicles with their little turbocharged four-cylinder engines, but I can tell you, when you come up behind the long semi-truck on a steep hill in Mexico or Uzbekistan, it’s sure nice to be able to drop down a gear and have that big turbocharged V8 pull us around instead of sitting there for half an hour. Check prices on the internet. A gallon of diesel in Turkmenistan was a dollar, but in Turkey it was four dollars. Obviously, we arrived in Turkmenistan with empty tanks.

Speaking of your fuel tanks, how large are they?

Gary: We have two Transfer Flow fuel tanks and two reserve cans on the back for a capacity of 80 gallons of diesel. That is an easy range of 1,000 miles. If there is a road anywhere in the world a thousand miles long, there will be diesel available or it wouldn’t be a road! The Turtle V will run well on any kind of diesel, jet fuel or kerosine. We have the factory fuel filter/water separator/fuel heater and an auxiliary Racor fuel filter/water separator/fuel heater with a clear bowl for daily inspection.

What tires do you have on your truck and what inflation values do you typically run?

Gary: Starting with an F-550 when we originally designed The Turtle V, it came as a dually. Dual rear tires do not work on bad roads. They pick up big rocks between the tires and they plow sand, snow and mud. One of the first big modifications we had to make on The Turtle V was to find a tire that would carry the weight, about 7,000 pounds per axle, as a single. We looked and tested two or three different brands and sizes and ended up coming back to the Michelin XZL. They carry our fully loaded truck down the highway at 55 psi. As soon as we leave the pavement we drop them down to 30 psi or even 25 psi depending on the conditions. Any other tire we tested of similar design like the Continental MPT needed 110 psi on the highway or they would overheat. Michelin XZL is a very unique tire.

You and Monika have an extensive resume of travel throughout the world. Tell us about some of your favorite places?

Gary: This is another question comes up quite often. Honestly it depends on the people and the climate and your personal outlook at the time. Certainly, I would go back to Mongolia or Tajikistan tomorrow because the people are so friendly and those countries are so magical in places. Southern Chile! I could live there. Traveling through Norway was a dream. Got to love Mexico! Do we have a special place? Not really. Where we live in the foothills of the California Gold Rush Country is pretty nice.

What’s been the scariest, most hair-raising moment you’ve experienced during your travels?

Gary: It seems like we should have had some really scary moments. Actually there haven’t been that many. I suppose one of the worst ones was crossing some thin ice on the Lena River when we drove up that river on the ice in the winter for 700 miles to cross Eastern Siberia. On one section we were several hundred yards from shore and we didn’t know how thick the ice was. We waited for another truck to come to see where to across the questionable area. Finally one arrived, and he waited to see where we would cross. That was some heart-stopping white-knuckle driving!

Do you have a website and/or social media channels that our readers can follow?

Gary: Sure! For people who would like to travel along with us from their armchair we certainly have a website, and it is full of information about how to contact the companies whose products we use. There are special adventures in different areas of the world. Our ongoing blogs will continue now as we ship our truck to South America and travel through Uruguay, Paraguay, Brazil, Bolivia, Peru, Chile and Argentina.

Do you have any other hobbies as they relate to the great outdoors or other special interests that you would like to tell us about?

Gary: What do we do in our spare time? As a team we love hiking, downhill skiing, cross-country skiing, and snowshoeing. We are both certified for diving and we both love cooking and experimenting with new recipes we learned from different countries which we have traveled through. After that, when we are home in Nevada City, there are always endless lists of projects that need to be worked on and Monika is an avid gardener. Getting our truck ready for its next adventure takes more time than we want.

Currently, probably our most interesting project, not really a hobby, is sponsoring the young girl that we had met in Tajikistan. We spend a couple of hours every week speaking with her on WhatsApp, 13 time zones away. She is making the amazing transition from being a young girl from a small village high in the Pamir mountains to a city teenager, going to one of the best schools in the country. When we visited her family last year in Tajikistan, without our truck, we became aware of how many other children there are like her who could really benefit from a good education. Consequently we started a Donor Box. Click here for more information. There is a wonderful saying: “If you want to touch the past, touch a rock. If you want to touch the present, touch a flower. If you want to touch the future, touch a life.” Sponsoring a young child that we met in the mountains of Tajikistan has been one of the most rewarding parts of all of our overland travels throughout the years. We have touched a life.

About Mello Mike 907 Articles
Mello Mike is an Arizona native, author, and the founder of Truck Camper Adventure. He's been RV'ing since 2002, is a certified RVIA Level 1 RV Technician, and has restored several Airstream travel trailers. A communications expert and licensed ham radio operator (KK7TCA), he retired from the U.S. Navy in 2004 as a CWO3 after 24 years, holds a BS degree, and now runs Truck Camper Adventure full-time. He also does some RV consulting, repairs, and inspections on the side. He currently rolls in a 4WD Ram 3500 outfitted with a SherpTek truck bed with a Bundutec Roadrunner mounted on top.


  1. Great interview. What a wealth of practical knowledge. I’m trying to find the black colored “hasps” shown on their rig’s rear compartment and cab door in the picture. I looked on their website and can’t find it. I found the pad locks, but not the hasps that attach to the vehicle. I marked up a photo, but couldn’t figure out how to post it. Anyone know what these are?

  2. Looking at the pix above of Monika and Gary, I hearken back to the time I saw their pix and they were in their 20’s. Time passes all too quickly when you are living the life. jefe

  3. Mike, this is THE best interview I have seen with the Westcott’s. I go all the way back to the late 60’s (that’s 1960 for you Millennials) and followed the Turtle (number here) adventures with them, when Gary was creeping around Mexico in his used Land Rover and a tent, trying to keep a transmission in the thing, and writing short articles for Pickup, Van and 4 wheel Drive magazine. Who remembers that rag? His then wife said, “This is not the life for me” and (I’m assuming) quietly excited. Gary was a lucky man to find the Swiss maiden, multilingual adventuress Monika along the way who had the same quest for adventure, writing, and photography in her heart. Jean my Queen and I live in the same town that they do (Nevada City) and have talked to them a couple times in the parking lot of the local hardware store. When you see their rig in the lot, you immediately have immediate recognition. They are the most cordial and agreeable folks you would ever want to meet. One fact is clear; they are the most famous, long lasting, and trend setting couple on the world traveling, off-road campmobile circuit today. jefe

Leave a Reply (You Must Be Logged In)