because these have centre diffs, they can be driven in 4WD high range (low range also on Land Rovers) on high friction surfaces without transmission damage risk
eg. Toyota wagons, Land Rovers, Range Rovers
all wheel drive:
Subaru
automatic or selectable 4WD systems:
various forms include automatic, torque proportioning, & selectable
Vehicle thefts may play a role in your vehicle choice
most commonly stolen in Australia
Holden Commodore VE
Ford Falcon
Toyota Corolla
Toyota Hilux
Ford Ranger PX
Holden Captiva CG
Vehicles with a keyless entry option unlock automatically when the vehicle’s key fob comes within a short distance of the vehicle
In typical keyless entry designs, the car transmits a low-frequency (eg, 135 kHz) radio signal to wake up any wireless keys within range. When a key fob receives this signal, it replies with a unique VHF (eg, 315 MHz) signal, and the car unlocks.
easy for thieves to replicate the frequency even if the key is inside the house - these should always be in a signal-blocking pouch or container, such as a metal tin
most commonly stolen exhausts and catalytic converters
all petrol cars manufactured after 1986 are required to have a catalytic converter, which controls noise and emission levels, depending upon car model, these can be rapidly stolen within a couple of minutes especially if there is good ground clearance, and then can be sold for around $200 at scrap metal yards (they contain rare earths such as 3-7g platinum, 2-7g palladium and 1-2g of rhodium worth a total of $AU1500 or more per exhaust) yet may cost you $6000 to replace!
thefts have sky rocketed since 2019 as metal prices have sky rocketed
in Australia:
Holden Commodores
Toyota Camry
Toyota HiAce vans
in Canada:
Hyundai Tucson
Honda CR-V
Hyundai Santa Fe
Kia Sportage
Mitsubishi RVR
in US:
1985-2021 Ford F-Series pickups
1989-2020 Honda Accord
2007-17 Jeep Patriot
1990-2022 Ford Econoline vans
1999-2021 Chevrolet Silverado pickups
2005-21 Chevrolet Equinox
1997-2020 Honda CR-V
1987-2019 Toyota Camry
2011-17 Chrysler 200
2001-21 Toyota Prius
2007-20 Subaru Outback
1998-2020 Subaru Forester
4WD vehicle - basic off road requirements
adequate fuel tank (eg. 90L)
ground clearance
approach & depart angles
sufficient wheel travel in the independent wheel suspension to keep all 4 wheels on the ground when traversing uneven ground ⇒?live wheels
firm suspension to cope with loads and repeated bumps
ENSURE your TYRE PRESSURES are DOWN to around 16psi or even to 6-8psi in soft sand before attempting recovery to give the most surface area
NEVER use the tow ball for recovery, it is not designed for that and if it breaks it could be lethal
REDUCE the forces needed by using a shovel to create a path in front of all 4 wheels
DON'T JOIN snap straps with a shackle - if the strap breaks the shackle becomes a flying missile
BE METHODICAL and CAREFUL
BE AWARE MOST cars do not come with Rated Recovery Points - the hooks are just there to tie the car down during transport
Use TWO Recovery Points if possible
AVOID RECOVERY using REVERSE - reverse gear in the gear box is not as strong and you risk damaging the gear box
AVOID the snatch strap if stuck in deep mud as there is a lot of suction and thus force needed - use the shovel, traction device and winch
USE RATED GEAR
usually 4.75 tonne bow shackles (3.25t for Subarus)1)
on Subarus, if the strap is too heavy for the weight of the car structural damage may occur to the Subaru monocoque ‘chassis’. A strap with a lot of stretch and rated up to 6000kg is suggested for a Subaru or other light SUV2)
4WD Accessories
lights:
most 4WD lights are inadequate for bush driving at night
consider replacing with after-market inserts to give better beam spread, whiter light & improved distance
don't fit brighter globes in moulded plastic headlight units as these will melt
consider auxiliary lights to replace the next to useless under-bumper fog lights, but may need to be wired to high-beam circuit
bull bars:
ensure specs are adequate to protect from animal strike as many are just for show
ensure strong enough to mount winch, lights, aerials
winch:
is a great insurance if you are traveling alone
power winch is a lot easier to use than a manual one
read manuals to avoid damage to driveline when driving on-road
if electric, may need additional battery capacity
alternatives:
wheel-based winch systems
Bush Winch from WA - only available for certain model 4WDs/2WDs and cost around $AU600
snow chains or similar to improve traction in bogs
tree protector (folded towel may suffice)
dampening device for protection if winch line breaks
chain saw to clear fallen trees
ground or sand anchor kit in case there are no solid trees (at least 4cm diameter if using a ground level system, much larger for higher systems) to winch from
essential to prevent potentially lethal missiles if rear is packed
fuel capacity:
only Toyota & Nissan make 4WD wagons with adequate fuel tank capacity
consider fitting a single larger tank rather than auxiliary pump as transfer pumps are unreliable
suspension:
heavily loaded vehicles may impact on standard suspensions
bar work & winch up front may require heavier front springs
tyres:
standard tyres on new 4WDs are usually inadequate for bush driving
in general, any tyres with 70-profile or 75-profile shape are too lightly built
larger diameter tyres don't give much more ground clearance (only the increase in radius not diameter!) but will cause other issues such as lower fuel economy, less stability
wider tyres look great but may perform WORSE than narrow tyres:
they do not give more traction on sand (the length of the contact as more important than the width)
may cause more resistance to forward motion on sand
may have a smaller traction contact area - often circular rather than ovoid
less able to “caterpillar” over rocks - many need to be deflated below 10psi instead of 15-20psi to gain deformation for better traction over rocks but pressures under 10psi are likely to result in tyre coming off the rim and other issues
are significantly heavier and more difficult to change
deflate tyres to about 1/3rd less than normal for dirt roads and to half normal for soft sand BUT you need to drive slower and re-inflate on bitumen otherwise you will risk them overheating and having a blowout.
deflate tyres to ~15psi on sand (9psi if bogged)
tyre pump to re-inflate after your deflation for off-road use
Twin pump compressors (the compression cylinders reach around 110degC after 10minutes!):
ARB - inflates from 18 to 38psi in 83secs drawing avg 55A at 78dB; will compress air into 22.4L tank to 150psi in 4min, and when used with tank to pump a tyre from 18 to 38psi takes 17secs at avg 60A
TJM - much heavier and more expensive, inflates from 18 to 38psi in 876secs drawing avg 80A at 76dB; will compress air into 22.4L tank to only 120psi in just under 3min but when used with tank to pump a tyre from 18 to 38psi takes 23secs at avg 70A 3)
traction aids:
all new 4WD wagons come with limited slip diffs (LSD's) or traction control as standard & for most people that is all they will need, (esp. if have Nissan Patrol or Prado diesel) however, serious off-roading you may need more (esp. if Toyota Land Rover):
stronger LSD
self-locking rear diffs (eg. Detroit NoSpin)
driver-controlled diff locks (eg. ARB's Air Locker)
towing:
automatic transmissions may need an oil cooler fitted to prevent over-heating
ensure you have appropriate topological maps +/- GPS
travel at appropriate speed for terrain:
too fast will cause:
shock absorbers to over heat if driving over corrugations
upset the passengers
miss seeing and thus avoiding obstacles or pot holes
you cannot memorise in 3D every obstacle in a path so if unsure have someone guide you past them
steep grades:
in general travel down the grade in same gear it required to get up it
ideally use engine-braking to retard speed downhill, but this is only possible on heavy-duty 4WDs that have deep-reduction gearing, most wagons, particularly automatics, lack sufficient engine braking
if you keep momentum low & the track isn't too slippery, light braking won't cause wheel-lock, if it does, get off the brakes quickly, then reapply lightly again
if you have ABS, the brake application needs to be heavier to make ABS work properly on all four wheels
if front wheels cannot be locked at same speed as rear wheels in low range then this can result in vehicle moving sideways!
make sure you do not end up sideways esp. when going downhill as this risks rolling over
beaches:
you are more likely to kill or be killed driving on beaches than any other off-road surface
driving too fast (usual limit is 30kph) then swerving
driving too fast on deflated tyres may result in roll over due to over-heated tyre coming off the rim
head on collision or running over people due to poor visibility (sun on sand creates disorientation) or distractions
the best sand vehicles are light
wet sand near the waveline may be hard but an odd soft patch can send you off-course without warning into the sea
know your tides, never drive along waveline on a rising tide best times are from 2hrs before low tide to 2hrs after
sand tyre pressures:
tyres deflated to half normal pressure are safe at only 40kph or so & even then won't respond to braking or steering as accurately
doing spectacular sand-splitting donuts as seen on TV ads risks blowout or tyre coming off the rim
finding the correct pressure is largely trial & error for a particular vehicle with a particular load, but most put lower limit at 16psi
never drive on roads at these pressures!
sand bogs:
tow using a web snatch - an elastic webbing robe that whips the car out of the bog
shovel out smooth ramps in front of each tyre first
if alone, then need to “roadbuild” with the vehicle jack using rocks, timber, shrubbery or sand and a winch is very helpful here
rivers:
always wade through the river first if you cannot clearly see the bottom as obstacles such as logs/rocks or deep potholes may cause problems
only attempt wading across if:
max. depth in metres x speed of current in m/sec is < 1, else you risk floating or drowning down the river
no crocodiles, etc
in general, cars should avoid water deeper than half the height of its wheels if you value your car!
engine requires constant flow of air to keep running:
ensure air intake is high enough
avoid stopping car as this risks stalling
ensure air conditioner is turned off so that radiator fan stops to prevent it getting distorted in water and damaging the radiator
if stalled in middle of deep river or caught in a rising tide at beach, first priority is getting everyone to safety!!
Assessing used 4WD's
this is notoriously difficult and probably should be avoided unless it is clear it has not been used off-road much, but some things to check for include:
determine what sought of life the vehicle has had:
front differential housing & underbody splash tray:
scratches & gouges show that it has done some off-road work
lubricant condition in front & rear diffs - any milkiness suggests water has entered housing, probably through a combination of a blown axle seal & the odd river crossing
noisy drivelines
shock absorbers:
an oil mist on them indicates blown seals
blistered or bubbling paint indicates shock has been very hot at some stage such as fast driving over outback corrugations which causes the shock's oil to break down & not work as well as it should
if suspension upgrade:
vehicle more likely to have been driven in rough conditions
firmer suspension also places greater loads on the mounting points & may result in fatigue-cracking, thus carefully check for metal cracks where the cabin is bolted onto the chassis.
if body is rubber-mounted to chassis (eg. Range Rovers), any looseness will cause the vehicle to feel sloppy
centre diff is critical to the driveline:
scalloping on outer edges of tyres as they tear themselves to bits on the road due to faulty (esp. Land Rover Freelanders)
any plates welded onto chassis rails are probably rust repairs or gussets added due to chassis cracking
tend to have 4-5L engines either V6 or V8, thus very poor fuel economy ~20L/100km
Toyota LandCruiser:
1st imported in 1957 to transport construction workers on the Snowy Mtn Scheme
200 Series
300 series replaced 200 Series in 2023-2024
Nissan Patrol
luxury vehicles:
Range Rover
Mercedes M-class
Dodge RAM
mid-size 4WD wagons:
6 cylinder 4WD as a good compromise between off-road & on-road driveability, but heavy on fuel consumption
by 2001, have 45% of 4WD market share with average price ~$50000-$60000
Jeep Cherokee - best blend of performance, handling, interior & off-road capabilities
Mitsubishi Pajero - almost as good as Jeep; 7 seats;
Nissan Pathfinder - slow, poor ground clearance, not roomy, old design but good build quality
LandRover Discovery - reliance on electronic traction & hill descent control impairs off-road
light “cross-over” 4WD wagons:
good on-road driveability with good fuel consumption, but still capable off-road although lack low-range gears
4 cyl or small (3-3.5L) V6
average price $35000-45000 2001
Subaru's Forester (1997) - low range gears
Mazda Tribute & Ford Escape (2001) - centre diff lock;
Nissan's X-Trail (2001) - excellent on-road; very roomy; new interior styling
luxury vehicles:
BMW X5 ($82,000)
compact 4WD wagons:
generally 4 cylinder vehicles, mainly for on-road driving, with limited off-road capabilities
Suzuki Vitara launched in 1988, was an early sign of things to come, with an avalanche of models appearing by the late 1990's, primarily used for city driving, stimulated by the launch of Toyota's fuel efficient RAV4 in 1994, but accelerated in sales in 1997
Honda's CRV (1997) - front-wheel drive which kicks in rear wheel drive when senses wheels lost traction. Poor off-road;
by 2001, had gained a steady 33% market share in 4WD market
all-wheel drive station wagons:
mainly for on-road driving, with limited off-road capabilities
Subaru Liberty launched in mid-1980's
Subaru Outback launched in 1996, transformed the soft-roader formula, setting the standard for “crossover” vehicles