Converting any vehicle requires time, resources and above all else, expert knowledge. We follow vloggers’, the Gap Decaders, year-long journey of converting their Overland Truck for their European journey, as told by one half of the couple; Izzy.
The Project
In early 2023, after six incredible years of full-time travel across the UK and Europe in motorhomes and an overland truck, we realized it was time to hit pause and spend some quality time with loved ones back in the UK. But the idea of sitting still for a year is not really our style.
So, we set ourselves an audacious challenge: build a brand-new overland truck in under 12 months for less than £100k – and document the entire journey for our YouTube channel. We already had a truck, but we wanted something bigger, better, and more capable for future adventures.
With a background in property renovations, 25 years of Phil’s experience working with vehicles in the Army (including off-road instruction), and my ninja-level resourcing and research skills, we felt confident we could pull it off. What could possibly go wrong?
The Base Vehicle
The search was on for the perfect 4×4 18t MAN or Mercedes truck – new enough for cab air-conditioning (a must after sweltering through a summer in the Caucasus and Turkey) but old enough to avoid AdBlue and complex electronics.
Easier said than done! Overland truck builds had exploded in popularity, and the best trucks were being snapped up. To make matters trickier, we were travelling in the Balkans, meaning in-person viewings weren’t an option.
Eventually, we found a 2008 MAN TGM with a crane on the back. After endless video calls, negotiations, and arranging for the crane and tipper bed to be removed, we bought it as a cab chassis.
Lesson learned: never buy a vehicle unseen! By the time we got our hands on it, we discovered it needed new injectors – an early and expensive setback for our already very tight budget.
The Habitation Box
Phil had a genius idea: instead of having a custom habitation box built, why not modify a second-hand truck freezer box? The plan was to cut it down and rebuild it with extrusions and new panels to fit our needs.
We struck gold, finding a well-insulated box in excellent condition, and even managed to sell the freezer unit for the same price we paid for the whole thing! A brand-new box would have cost around £20k, but with some creative rebuilding, we spent just under £4k.
However, this part of the build was a massive time sink. Stripping and modifying the box took months, with Phil spending a full week just removing the industrial-strength adhesive from the internal shelving.
Fabrication
We quickly learned that fabrication is a whole world of pain and expense. At the very least, a bespoke overland truck build requires a custom sub-frame – the crucial component that allows the habitation box to flex with the chassis rather than snap in half. Not something you could claim on your insurance.
Working with a professional coachbuilder, we designed the sub-frame and other metal work, including access steps, a bike rack, a spare wheel carrier, mountings for a new 600-litre fuel tank, tool bins, and the all-important cut-through between the cab and hab.
But we underestimated just how costly metal fabrication could be. Every monthly bill was a shock, often requiring a stiff drink to recover.
The Marriage
With the sub-frame complete, it was time for the big moment – the ‘marriage’ of the box to the chassis. Watching it being hoisted by a crane, adjusted, and lowered repeatedly was a nerve-wracking experience. Every millimetre mattered to ensure a perfectly straight and level fit.
There was no room for error as we had a paint shop booked for the next day. After much deliberation over the perfect colour, the truck spent ten days in the booth, undergoing its transformation. When it finally emerged, it looked every bit as incredible as we had envisioned.
Layout & Design
While Phil tackled the physical build, I focused on the interior layout. Every space, no matter how small, counted, especially with bulky components like plumbing, heating, and electrics.
The moment of truth came when Phil cut openings for doors, windows, and access hatches. Unlike in a house renovation, where there’s room for adjustments, here there was no margin for error. My measurements had to be spot on.
Luckily, they were, but we didn’t know for sure until we started fitting the internal elements.
Electrics & Plumbing
With the truck off for its Victron solar system install, we took a much-needed week-long breather. Once back, Phil dived into plumbing, squeezing a complex system – including a massive 500-litre fresh water tank – into a neatly organised space under a bench seat.
We installed an Eberspächer for hot water and wet heating, complete with the luxury of underfloor heating, plus a Chinese diesel heater for an instant blast of warmth on chilly mornings. A 40-litre calorifier with an immersion element was added for days when surplus solar power could be used to heat water.
At some point, we’ll also add a heat exchanger which will work as we’re driving, meaning we’ll arrive with a tank of hot water and a warm and cosy box.
In that tiny space, we also managed to fit a full water filtration system, allowing us to safely fill up from virtually any source and have 100% clean drinking water.
Internal Fit-Out
Suddenly, it was full steam ahead. The finish line was in sight, and time was slipping away. Originally, we planned to build the cabinetry ourselves, but in the end, we called in a local cabinet maker who did a far superior job.
Next came the exciting part: installing taps, sinks, the shower, and toilet, bringing the truck to life with heat and running water. Outside, we fitted a pull-out BBQ, underslung gas tank, and chassis-mounted grey waste tank.
As the second-fix electrics wrapped up, we finally added the personal touches – upholstery, a mural above the bed, and, of course, the daunting task of packing everything in.
It was a bittersweet moment. The truck was ready, but it also meant saying goodbye to friends and family.
Did We Meet the Challenge?
Yes and no!
We completed the build in just under 11 months, smashing our 12-month target. But our £100k budget? Not even close. The final bill came to £150k, thanks to skyrocketing material costs, underestimated expenses, and the sheer amount of work required.
Phil alone put in 60-hour weeks for nearly a year. If we had paid him a salary, his labour would have cost a fortune. Luckily, he works for passion, not a payslip.
Getting on the Road
At last, we were ready to roll. After updating the DVLA on our new body type and taxation class, we organised insurance through Sterling. We’ve always had excellent service from them and they’re not phased by the size and scope of the truck. It feels like they get us and how we want to travel.
And just like that, we hit the road for Spain, ready for the next chapter of adventure. The journey was tougher (and pricier) than we imagined, but the end result? 100% worth it.
Izzy and Phil blog and vlog about their travels and overland life as The Gap Decaders.
Insuring your motorhome
Whatever time of year you’re travelling in your motorhome, you’ll want the correct insurance. Sterling offers a range of motorhome insurance policies for you to pick from so you can find what works for your vehicle.
You can call our advisors on 0344 381 9990, or book a free callback at a time that’s convenient for you.
