Our new (GXV-Unimog) vehicle
Our choice of a new adventure vehicle came on the heals of a good experience with our Provan Tiger during our 19 month 60,000 mile Americas Trip and in the face of a, then recent, purchase of, and happy experience with, a used 2008 Earthroamer.
Not long after purchasing the ER, with the adrenalin of Overland Expo 2011 still flowing in our veins we decided a new multi-year multi-continent international adventure was called for.
That raised the question of whether the ER was the right vehicle for the proposed adventure or should we be considering something different.
Ultimately we chose to sell our Earthroamer (it is still available as a consignment sale on the Earthroamer website if anyone is interested) and commissioned a vehicle from Global Expedition Vehicles (here after called GXV).
GXV sourced a 2003 Unimog U500 for us and we contracted them to fit out that chassis with one of their Safari camper box and a range of other goodies.
The how and the why of that choice, the build up of the vehicle and our ongoing experience with that choice is detailed in the sections (tabs) of this article.
I will add to this article as time goes by and our experience with the vehicle and its associated equipment grows. Those following by RSS or email will get notifications whenever a significant addition/modification is made.
Maintenance and Repairs
The topic that got me started down the path of "another vehicle" was the question of availability of maintenance and repairs.
Our Tiger-Chevy Duramax was incredibly reliable in South America, BUT it was clear from conversations with Chevy dealers in various countries that repairs on the engine/transmission would have been very difficult. Those vehicles, the Duramax engine and Allison transmission are not used in any commonly available vehicles in those parts of the world.
The situation seemed no better with the Earthroamer's Ford chassis. Dick Smith's experience with his 6.0 PSD Earthroamer in Mongolia (see this link) may be an extreme; but unlike Dick we don't have the money to fly Ford mechanics from the US to fix mechanical problems.
It is worth noting that the Smiths and their Earthroamer did complete their trip around-the-world and at least one other Earthroamer ( see globalroadtrekker.com) is currently undertaking such an adventure. So my concerns may well be "obsession" rather than realistic.
GVW, Tires and suspension
Vehicle GVW, tire load rating and suspension modification was the second topic that got me thinking of "another vehicle".
Our Tiger was pretty much at maximum GVW all the time. That was not a result of us carrying a lot of stuff simply the result of the camper body on a 1-ton pickup. The consequence of that loading was that at the rear the tires were running at their load limit and wore relatively quickly. Had I stayed with the Tiger I would have considered an upgrade to 19.5" wheels like the travelin-tortuga.com , but that may have involved some suspension mods and maybe re-gearing.
Our Earthroamer was also running close to GVW but at least with those 22.5 wheels and Michelin tires there was plenty of excess tire load rating.
The initial wish list
I concluded that I should look for a camper built on a Mercedes truck with a GVW of over 20,000 lbs, tires that could handle the our traveling weight and the vehicle GVW and no suspensions modifications.
Why a Mercedes?
The most colorful explanation of this I have ever read is from Jim Rogers. He and his wife drove a yellow Mercedes sports car around the world in 1999, 2000, 2001. He argued (something like) "when dictators take over a country the first thing they do is buy (stolen) Mercedes cars". Hence even poor countries have Mercedes dealers.
It is (probably?) not true that there are Mercedes truck repair facilities everywhere, and a Unimog is only a "sort-of" Mercedes. But I still buy the argument, that a Mercedes truck will be easier to get parts for than a US Ford or Chevy.
GXV's Global Traveler
In August of 2011 we visited the GXV factory in Missouri primarily to look at their Global Traveler vehicle.
This is "typical" European style expedition camper; a forward control truck with a camper box on the back. The truck itself was a Mercedes 1017 with factory 4x4 and factory rear locker. The only modification to the truck was a conversion to 20" wheels all round and singles (rather than duallies) at the rear. This truck is commonly used by Europeans for expedition campers so I felt confident that it was a good candidate.
In the flesh the truck was less than I had hoped for. No creature comforts (the F550 Lariat package on our ER had somewhat spoiled us) including no A/C and no cruise control. A bit low on power and gearing for extended highway travel.
If we chose this option GXV would have to source a truck for us in Europe and import it under the 25 year rule. The all up cost to get a 25 year old truck was approaching that of a new F550.
All in all the truck was not as strong a candidate as I had expected. But the camper box it self was great, well made with plenty of storage and top line equipment.
Enter the U500 vario-pilot
The only other realistic option for a "Mercedes" here in the US was a Unimog U500. We knew from previous conversations that Mike was very familiar with the U500 and thought very highly of them. Nina and I on the other hand had viewed them as a bit O-T-T (over-the-top).
While discussing all of this with Mike and Rene Van Pelt they mentioned the vario-pilot feature available on some Unimog U500 trucks.
For those that don't know about this (as we did not at the time) it is a little un-believable. It is a feature that allows the driving controls (steering wheel and pedals) to be moved from one side of the vehicle to the other. Moreover this transformation takes only a few minutes.
This gave us the option to take the truck and camper back to Australia with us as the vario-pilot qualifies as right-hand drive. Other vehicles like the Chevy or Ford would probably require a steering conversion to be eligible for Australian registration.
The vario-pilot was a significant factor in our final decision. Whether we will eventually take or U500-GXV back to Australia or not only time will tell. But the option to do so seemed valuable.
Just to complete the picture. The U500 have a 33,000lb GVW, is factory 4x4, and comes with 395/85R20 tires which will carry the 33,000 GVW.
So in late August 2011 Mike with the help of Rob Pickering found us U500 with the coveted vario-pilot and we were on our way to yet-another-expedition-vehicle (YAEV in the language of linux nerds).
For those like me that don't (or at least did not) know much about the Unimog U500 I am including some spec sheets and a general discussion of the vehicle. It is worth noting that I could not find a spec sheet for a 2003 vehicle so have resorted to a document published in 2009. This later model vehicle has a Euro 5 engine (and as such required BlueTech fluid and ULSD fuel) rather than Euro 3 engine in our vehicle which has no issue with high sulfur fuel.
To read the specs click on the thumbnail image and then cycle through them with the next/prev tabs.
Our particular U500
The particular vehicle we acquired has the 8-forward 6-reverse speed Telligent manual transmission, plus both "working gears" (thats low range) and "crawler gears" (thats super low range).
I got a real kick from the spec sheet. Top speed in the crawler gears (with the transmission in 8th or top mind you) is 15 kph. I am looking forward to trying out those crawler gears to see just how slow they are.
Our vehicle also has the up rated engine (286HP), an uprated chassis at 33,000 GVW and 395/85R20 tires. It does not have CTIS (central tire inflation system) and I am probably a little disappointed abut that.
Oh, and by the way the truck is YELLOW, the camper is also. We will look a bit like a bummble bee coming down the road.
We commissioned the following modifications to the truck.
The wheelbase has been extended from 153" to 181" to accommodate the camper box without an exceptionally large overhang or steeply sloping rear. This required an extended rear driveshaft and intermediate bearing block.
An additional fuel tank with a capacity of 100 gallons has been added giving a total fuel load of 160 gallons. I am hoping to get the range up towards 1,500 miles.
A Webasco 90 ST hydronic heater has been installed. This provides hot water to the camper while the truck is running and can also heats the truck coolant when the truck is not running. The camper heating is derived from hot water, but more on that later.
A sliding metal door was put in the back of the truck cab to facilitate entry into the camper from the driving position.
We added a RedDot roof mounted air conditioner to the truck cab as we had doubts about the effectiveness of the Unimog stock A/C in extreme conditions. The vario-pilot takes up some ducting space and seems to have the side effect of reducing the effectiveness of the stock AC.
Finally, the three point mounting system that connects the camper to the truck had to be installed. Is this a truck mod ?.
A winch - the mod we did not (yet) make
It probably seems strange to many that we did not (or maybe it is "have not yet") fitted a winch to our Unimog. After all this vehicle is such a 4x4 icon it is almost sacrilege not to put a winch on it, even if only for the "look". To top it off Warn even make a hydraulic winch specifically for the Unimog.
My reasoning is simple. The Warn Unimog winch is about $5000, and has a pull rating of 18,500lbs. The vehicle will be about 24,000 lbs all up. All the recovery experts tell me that the winch should have a pull 2x to 3x the weight of the vehicle. Thus on that basis I need a 40,000 - 60,000lb rated winch. Such a winch will cost a lot more that $5000 and will weight hundreds of pounds. Thus I will wait and see if a winch is needed - after all I plan on overlanding not rock crawling.
We chose to have GXV build and mount a Safari version of their camper box. You can get the general dimensions and layout of this box from the drawings in the images below (just click the thumbnail to get a larger view).
In broad strokes the camper box (not the overall vehicle) is 15.5' long, 8' wide and just shy of 8' high. The internal layout is pretty much a GXV standard arrangement.
With those camper dimensions the overall vehicle will be (understand that at the time of writing it is not complete) about 26' long, 8' wide and 12'10" high.
The key choices that we made for the camper are:
The step down door. We decided to have a drop down for the camper door with an electric auto opening step to make entry easier. I regretted using the chassis space and the perceived reduction in clearance, but my wife at 5'1" would find a door 4' off the ground too hard to manage.
The square tail on the camper. Many expedition trucks have a sloping or angled tail on the camper to provide a better departure angle and aid in exiting from ditches and gullies. We decided early on that we would sacrifice that additional maneuverability in favor of greater internal storage. We regained some of our departure angle by having the truck wheelbase extended.
A Onan Q3200 diesel generator mounted inside (but isolated from) the rear storage area.
This is really three decisions.
The first decision was whether to have a generator. That we would have one and that it would be diesel was never in doubt. Boondocking in hot weather without A/C is just not my idea of fun.
The second decision was to use an Onan. GXV has typically used Fischer-Panada generators in their builds, these are sophisticated liquid cooled units that seem to be used a lot in small yachts. I preferred to go with something simpler.
Mounting the generator inside the camper body. GXV typical mounts the generator on the chassis below the camper body. I preferred to have the chassis space available for an additional fuel tank and to keep the generator up away from any water for what we hope will be in frequent water crossings.
A pass-thru between the truck and the camper. This was also never in doubt. In our opinion this feature is a major convenience/requirement when camping in bad weather or in urban locations.
Roof rails on the camper body. These are metal tubular rails along the leading and upper edges of the camper to protect the camper body somewhat when we inevitably run into some substantial tree branches.
A large rear carrying rack that can accommodate more than just the spare tire and its associated small winch. Seems like a good place to carry fire wood, maybe additional fuel and nomadic hitch hikers.
Glass not acrylic windows. We had the experience in the Earthroamer of scratching the window panes on tree branches while driving on forest trails; did not want a repeat.
Also the windows we chose have provision for metal security inserts to make the windows proof against breakin.
Camper equipment and fittings
All the other stuff that goes into making a camper is pretty much standard GXV.
Hot water is provided from the chassis mounted Webasco 90 ST hydroponic heater. This unit is either diesel fired or heated by the engine coolant. It feeds a hot water Isotherm storage tank under the sink area.
A hot water radiator and fan unit mounted under the dinette is the primary source of camper heating. The fan in this unit forces air over the hot water radiator and circulates the air around the camper.
A small electric heater used in conjunction with the generator is the backup heat source.
There is no heated air system as found in a typical RV.
A 13,500 btu roof A/C unit is included. It requires the generator to be running or shore power.
The Vitrifrigo refrigerator is somewhat unusual for an RV as it has two drawers rather than doors. The top drawer is a freezer compartment and the lower drawer is the refrigerator compartment. It operates from the 12Volt electrical supply.
The electrical power system is quite something.
The heart of the system is a battery pack consisting of 3 x 250 AH glass mat deep cycle batteries.
The batteries are fed by
2 x 180 watt solar panels,
the truck alternator while on the road
the generator when it is running
shore power of either 110V/60Hz or 230V/50Hz through a universal/world charger.
The batteries feed into a 3.6 kw inverter
All ac appliances operate on 110V/60Hz and a fed by the inverted, or by a direct shore power feed when shore power is 110V/60Hz.
The battery pack is wired into the truck starting system and can be used to start the truck engine in an emergency.
All lighting is LED.
The toilet is a 5 gallon canister type. Great for boondocking and operating in environments that don't have typical RV park hookups.
The shower and kitchen sink empty into a 25 gallon gray water tank.
Entertainment equipment is relatively sparse. The camper has a radio/cd player and the truck has a satellite capable radio with CD player and iPod connection.
These days almost all of our entertainment comes through our iPads, Kindles or MacBooks.
- Finishes and Furnishings
The finishes are nice but simple. The bathroom cabinets and shower grate are teak. All other cabinets are maple. The floor is covered in a woven nylon that is easy to clean and sturdy. Counter tops are granite. The walls retain the white gel coat finish of the composite panels that the camper shell is made from.
This page is still under construction. But to give you something to look at I have provided some photos of the camper interior during construction.
We took delivery of the completed vehicle the week beginning May 7th, 2012. I spent most of that week at the GXV premises learning about the vehicle, dreaming up new things for them to do and completing the usual paper work.
I have include some images of inside and outside the vehicle
This page is still under construction
This page is still under construction