New Tires

Sterlin is fitted with Grabber AT2 tires from General Tire.  Basically a stock tire that is a little wider than normal and with a more aggressive grip for both on and off road driving.
The Vehicle Dependent Expedition Guide (VDEG) by Tom Sheppard recommends the following:-

• Tubed Tires. Our tires are in fact tubeless. Apparently tubeless tires save weight, cost and puncture less dramatically. But they require specialist equipment to fit and large amounts of high pressure air to fill.
• One spare. To quote our venerable VDEG, "A single spare wheel and tyre is perfectly adequate for expeditions in even the most distant region; quite simply, the weight, bulk of one spare wheel is quite enough of a handicap when you are pushed for payload".
• Radial Ply Tires.  Our tires are radial ply.  See below for more details of the tire constructions.  Radial Ply offer lower rolling resistance gaining detectably better fuel consumption as well as permitting lower inflation pressures without overheating.

The choice of tire is quite important as they are bound to fail at some point on the journey. We will be on tarmac, tracks, mud and desert so a good all-round tire is preferred. Ideally we would have a tire like the Michelin XZL, but the Grabber AT2 is an ok alternative.

In terms of wheels or rims, we have the tires fitted onto factory alloy rims.  All wheels are configured the same in terms of both tires and rims. The rims are secured to the car with McGard wheel locks. Some specs for our tire choice.

• Brand: General Tire
• Model: Grabber AT2
• Size: 255/65R-16
• Type: Mud and Snow
• Load/Speed Index: 109T (1,030kgs/2,300lbs, 190kph/118mph)
• Load Range: Standard Load
• Sidewall: Outline White Lettering
• Overall Tire/Wheel Diameter: 29.1 ins.
• Tire Weight: 37.0 lbs
• Max Inflation Pressure: 44 psi
• Overall Section Width (measuring rim): 10.2 (7.5) ins.
• Approved Rim Widths: 7.0 - 9.0 ins.
• Max Load: 2271 lbs
• Tread Depth (32nds): 16
• Revs per Mile: 714
• RIM Protect: yes

Info-graphic of the tires we are using.

Sand Tracks

Sterlin has aluminum sand tracks or sand ladders mounted on the roof rack. These are not really carried to free us from sand or soft ground, but rather are there in case we have to create a bridge across rutted or uneven road surfaces. We purchased our sand tracks from www.OKoffroad.com

Jerry Cans

We added 4 Jerry cans for fuel and to extend the range of the thirsty discovery engine. Land Rover Discoveries have very poor fuel economy achieving around 15 mpg or 15.7 l/100kms.  So a full fuel tank provides a range of around 375 miles or 600 kms.  The four Jerry Cans will extend the range to a total of 675 miles or 1,100 kms.  Still not great, but better.

We had read in Lonely Planet that there are fuel availability issues in Mongolia and Uzbekistan. And maybe they would be useful in Australia. Turns out we never had issues obtaining fuel. We did fill the Jerry cans once, just before we crossed from China into Mongolia as a precaution. And this is when we discovered that the particular Jerry cans we purchased had a major flaw. They leak. The fancy pouring spout has to be installed facing out, otherwise the can will leak badly. But with the spout facing out, the cans can't be secured in the carriers. We quickly transferred the fuel back into the main fuel tank and never used them again for car fuel. We did carry a small amount fuel for our stove in one of the cans.

Also, we were quite worried about the extra load on the roof rack. Not because of roll over, but not sure if the rain gutter would be strong enough. So again, lucky we never had to use them. The alternative to Jerry cans was to fit a second fuel tank. But that would have been a considerable undertaking, and glad we did not bother with that.

The current thought is to sell or give away the cans in Belgium and not return to America with them.

Jerry Cans on Roof Rack

Driving Lamps

Sterlin has been fitted with two extra driving lamps mounted on the front brush bar. The thought is these lamps will mainly be used to light our camping area.  But, in the unlikely event we drive at night, they might came in handy.

My brother, Hamish, helped with the installation, which took the most of an afternoon. Bolting on the lights was the easy part, trying to thread the control wiring through the engine bay wall into the passenger area was the hard bit.  But we got it eventually.

The lights are Hella 500 12v/55W and are connected to the auxiliary battery and can be switched on and off from the drivers seat.

Hella 500 Driving Lamps

Related Posts

• Dual Battery and 12v Distribution

Water Tank, Filter and Pump

Sterlin is fitted with a 50 liter (13 gallon) clean water tank which is connected to an electric pump which pumps the water through a water purification or filter system. 

The plan is for the water tank will always hold clean water. To achieve this, we will filter all water before it goes into the tank by using the pump and filter system. And as an added precaution, we will also filter the water when we pump it from the water tank for use.

Components

The first major component is a water tank from Front Runner which  is made from food grade polyethylene and is BPA free. Although the tank construction is very solid, unfortunately the metal outlet valve leaked and we replaced it with a new fitting. The other problem we had to address was a way to let air into the tank to replace the water which is pumped out. Unless we did this, the pump would create so much suction that the tank would collapse in on itself.  One way to address this is to merely open the filling cap when in use. But we need to remember to open and close the cap, which seems unlikely. So instead, we fitted an air intake valve into the cap.

The second major component is a water pump.  We selected the Revolution water pump from Shurflo  which is capable of producing 3 gallons or 12 liters per minute at a draw of 7.5 Amps from the 12volt system. More useful is that the pump will automatically cycle on and off based on demand and will even run dry without damage. The water pump is on its own 12volt circuit with an isolation circuit so it can be turned off at night and while driving. When turned off we also relief the built up water pressure in the hoses to prevent leaks.

The last major component in our clean water system is the filter. We selected the Doulton RIF-10 which is a 0.2 micron ceramic filter capable of filtering out pathogenic bacteria such as E.coli, salmonella etc. It will also reduces dirt, chlorine taste and odor, mold, algae and removes 100% Cryptosporidium and Giardia cysts. Typically there is also a sediment filter before the activated carbon and ceramic filters to protect them. But to save space, we did not install the sediment filter. Halfway through the trip we switched the order of the two filters, using the ceramic filter to protect the activated carbon as it is easiervto clean the ceramic filter. The recommended installation order is the other way around.

The three major components are connected with various hoses, piping, valves and fittings.  The water pump and water filter system are mounted on a wooden panel with a simple detachable mount which enables them to be electrically and hydraulically disconnected and removed from the vehicle for cleaning or operation outside the vehicle.

Operation

The operation of the system is very simple.  To start the flow of clean water the outlet valve is opened, the pump detects a drop in discharge pressure and automatically starts and the water flows. To stop the flow the outlet valve is closed, the pump detects a rise in discharge pressure and automatically shuts off after a few seconds. The main trick is to avoid accidentally opening the discharge valve when the pump is enabled, which results in water going everywhere.

Filling the water tank is also a simple system. The inlet side of the water pump can be connected either to the water tank or a external source for filling. The water tank and the external source connections both have an isolation valve, which is typically closed. We connect a short piece of hose pipe to the external connection point, open the valve during the filling process. The short piece of hose pipe is long enough that we can drive our car into a river and directly fill from the river. More typically the water source will be from a hotel and we have a portable and collapsable water bag so to can carry the water from the hotel to our car.  We will have to repeat this process a number of time to fill up an empty water tank.

We will not maintain a log of water usage as recommended, as the water filter we selected is rated for 50,000 liters which far exceeds our possible usage.  We will however inspect the filters every month and clean them as necessary and drain the water tank and clean it.

Fire Extinguishers

Sterlin carries two fire extinguishers.  The first line of defense is from a H3R clean agent fire extinguisher with 2.5lb of agent.  The unit is mounted on the storage box behind the passengers seat.  The second fire extinguisher is stored under the passenger's side seat.

Stainless Steel Rear Cargo Door

We replaced Sterlin's original rear cargo panel with an upgraded stainless steel panel and added a fold down work table. The replacement panel is from Columbia Overland and is purpose built for the Land Rover Discovery II.  The fold down table is made by Outback Adventures, Inc. It took many months of thinking and considering many options before we selected this simple arrangement. The first idea was to construct the fold down table ourselves, but the product from Outback Adventurers was far superior to anything we could build. So glad we did build our own.

The fold down table is very sturdy and provides ample room to prepare food or even act as a shelf for the stove.  There is a nice bamboo slide-out section which allows the table to be extended. Although this table was designed for a JK Jeep, it works perfectly fine on Sterlin.

Dual Battery and 12v Distribution

Sterlin now has two batteries, one battery for the engine and a new one for auxiliaries. The auxiliary battery is installed in the engine bay next to the main battery. The two batteries are electrically connected via a charging solenoid. The auxiliary battery power is used for: the fridge, clean water pump, spot lights  at the front of the car, outlets installed on roof rack for extra lighting and various other things, like chargers.

Should you want to know more, this post provides a lengthy description of the installation.