are two reasons you might choose to build a hardcore 4WD.
builds generally push the boundaries on road legal, and I would strongly
recommend getting it engineered for insurance and legal reasons. It may involve
a lift between 2 and 4 inches, and much bigger and more aggressive tyres than
Modified Jeep Wrangler.
2: A Comp Truck
Purposely built for
competition use, this type of hardcore 4x4 build would usually be unlicensed
and be transported on a car trailer. They can’t be used on roads, in national
parks or state forests; they are usually kept to private property and the
The 5 Major Hardcore 4x4 Modifications.
1: Suspension (4x4
A hardcore 4x4 lift kit could be between 2 and 4 inches above factory,
or even more for a competition truck build. Keep in mind that only up to 2 inch
lift (50mm) is street legal, and any bigger will require engineer certification
if you don’t want to attract a defect notice. The higher you go, the more
likely you’ll be picked on by the authorities.
For more detail see Lift kits & Suspension.
2: Bigger wheels
Bigger tyres are
the only way to raise the lowest points of the 4x4, very important for hardcore
4x4 modification. If the vehicle uses an independent suspension setup, this
will limit how big you can go. Live axle 4x4s have much greater choice.
If fitting tyres
more than 3 sizes bigger than stock, you may want to change the final gearing
(which is in the differential). Larger tyres will mess with the final gearing
making the vehicle not as great in low range. It will be harder to crawl over
rocks, you’ll apply the brake more on hill descents, and work the clutch
It will also sit outside
the rev range it was designed for on the road, which can make fuel economy
better OR worse.
For more information see Tires & Wheels.
3: Bar work &
A hardcore 4x4 is
set up to be driven over rocks, deep ruts and logs, so it should be armoured up.
Bull bar is number one, and
bash plates are a must to protect those low-slung parts. Unless you don’t care
too much about body work, you’ll want some brush bars and rock sliders to
protect your panels too. And a rear bar will save your back end from knocks and
scrapes in technical terrain.
For more detail on bar work and armour click here.
4: Traction Aids
Combine lift and
some larger, aggressive tyres with diff lockers, and now you’re REALLY getting
into hardcore 4x4 modifications! Differential lockers used correctly will help
prevent driveline damage, allowing you to crawl slower over technical terrain
while maintaining traction at all wheels.
When an open diffed
4wd encounters a situation with no traction on opposing diagonal wheels – all
of the drive is sent to the wheels with no traction, while the ones on the
ground do nothing.
Engage a diff
locker however; and this forces wheels on the same axle to spin at the same
rate. Now those wheels planted on the ground have drive again, and you’ll crawl
right through like it was never a problem.
For more information, see Diff
What fun is a hardcore 4x4
if it doesn’t see a bit of mud from time to time? A snorkel is a must because
unless you walk it (yuck) you never really know how deep that bog hole is.
For more details on Snorkels click here
What comes after the main modifications?
After you’ve sorted
out the main hardcore 4x4 modifications the sky is the limit. Here are a few
more items you might like to build into your ultimate 4x4.
There are two main
winch options for this type of 4WD setup:
Standard winch (single speed, slow only)
Competition winch (two speed, slow or fast)
To get the most out
of your hardcore 4x4, you’ll probably want to do some hardcore night driving! A
set of spotlights is commonplace on most 4WDs, but you might also add flood
lights facing sideways and rearwards, or rock lights that illuminate your
wheels and underbody for the really technical terrain.
We touched a little
on gearing with tyres, but if you’re getting right into the low and slow rock
driving, you might like to fit a set of reduction gears to allow your 4x4 to
move even slower, with higher torque for technical terrain
This could be
anything from an exhaust to a tune for more lowdown power, or a complete engine
Click these links
for more information on Recovery
Points, Winches, Engine
Mods and Lighting