The 9 Best Underbody Protection Kits in Australia

If you’re serious about 4WDing, you’ll know how important protecting the underside of your 4WD is. There’s a lot of vital components sitting under your feet, and a hole in your radiator or a damaged transfer case can be disastrous when you’re a long way from help.

Most 4x4s come from the factory with minimal underbody protection. At best, they’ll have thin sheetmetal guards. And many manufacturers only protect the engine sump, leaving the gearbox and transfer case completely exposed.

Thankfully, the aftermarket guys have you covered. You can get a kit for just about any make and model of 4x4 running around our roads.

The kits vary from basic sump guards to full underbody protection (rear diff housing guards are extra). To narrow down the selection, we decided to focus on suppliers who provide full underbody protection kits.

Once you’re armed with this information, you can decide whether you need the full kit or only selected components.

Note: We’ve included a ‘Typical Weight’ in our Specifications. It’s just an indication – weight will vary between vehicle makes. We took a ‘typical’ kit and used this to compare weights between the suppliers.

IRONMAN 4x4 UNDERBODY PROTECTION

Ironman 4x4 Underbody Protection

• Material: Steel, EDP E-Coated and powder-coated
• Thickness: 4mm folded steel construction
• Typical Weight (indication only): 25-30kg
• No-drill: Yes
  
  

Find out more at Ironman 4x4

Ironman 4x4’s Premium Underbody Protection kits are made from 4mm-thick steel, EDP E-Coated and then powder-coated black for extra protection and looks.

They feature recessed high-tensile hardware which removes the chance of being hung up, and have been designed to far exceed the strength and protection provided by OEM equipment.

The Premium range of underbody protection from Ironman 4x4 incorporates service inspection holes, and is available for a range of popular four-wheel drives.

CUSTOM OFFROAD UNDERBODY PROTECTION

Custom Offroad Underbody Protection

• Material: Stainless steel with 2B finish
• Thickness: 3mm or 4mm
• Typical Weight (indication only): 25-30kg (3mm), 35-40kg (4mm)
• No-drill: Yes
  
  

Find out more at Custom Offroad

Custom Offroad underbody protection kits are designed to bolt straight on. If a factory kit fits, then one of their kits will fit your 4WD.

They’re made from stainless steel, meaning no corrosion issues and greater strength than an equivalent product made from mild steel.

Depending on the level of protection you need, they’re available in either 3mm or 4mm thickness. Typically, a 3mm protection kit will weigh between 25 and 30kg. The 4mm version adds around 10kg when compared to the 3mm kit.

Custom Offroad makes its underbody kits at its Brisbane factory and deliver Australia-wide. You can fit them yourself or get one of their approved installers to do the job instead.

FRONT RUNNER UNDERBODY PROTECTION

Front Runner Underbody Protection

• Material: Stainless steel, powder-coated
• Thickness: 3mm
• Typical Weight (indication only): 30kg
• No-drill: Yes

Find out more at Front Runner Outfitters

Front Runner is based in South Africa, with a proven background in supplying rugged gear for its local market.

Its underbody protection kits are made from 3mm-thick stainless steel, then powder-coated black for extra protection and looks. Instead of pressings, Front Runner folds the plates then uses welded ribs for extra strength where needed.

A quality product with a reputation for toughness in the worst conditions.

TJM UNDERBODY PROTECTION

TJM Underbody Protection

• Material: Stainless steel, powder-coated
• Thickness: 3mm
• Typical Weight (indication only): 30kg
• No-drill: Yes

Find out more at TJM

TJM supplies a range of underbody protection kits made from 3mm-thick mild steel. They’re electroplated then powder-coated for corrosion protection. The individual guards are pressed and folded for added strength. Ventilation slots allow cooling air to get in, and mud and water to get out.

Shrouded bolt heads protect the vulnerable bolt heads from damage, meaning you don’t need to worry about snapping off bolt heads or damaged bolts.

The only downside? Once you scrape through the electroplating and powder coating, the mild steel is exposed to the elements.

KAON UNDERBODY PROTECTION

Kaon Underbody Protection

• Material: High-strength mild steel
• Thickness: 3mm
• Typical Weight (indication only): 20kg
• No-drill: Yes

Find out more at Kaon

KAON is an Australian company based in Queensland. They use high-strength structural steel, which enables the underbody protection kits to be thinner and therefore less weight.

All plates are powder-coated after cutting and folding for additional protection … although once the powder-coating’s damaged, it exposes the bare metal underneath. KAON provides plenty of ventilation/drainage slots in the plates.

And it understands the importance of recessing the heads of the mounting bolts. This gives you peace of mind that you won’t snap off a bolt when you’re sliding over a large rock.

ARB UNDERBODY PROTECTION

ARB Underbody Protection

• Material: Mild steel, zinc plated or powder-coated
• Thickness: 3mm
• Typical Weight (indication only): 30kg
• No-drill: Yes

Find out more at ARB

Pressing enables ARB to incorporate stiffeners in the plates without additional components. So they can achieve maximum strength from the relatively lightweight 3mm steel.

Not so good is the use of zinc plating or powder-coating. Scratches aren’t easy to touch up without it being obvious you’ve done a patch-up job … and once the coating is damaged, the mild steel is exposed to the elements.

You’ll also need to remove the plates before an oil change. Not a biggie, but worth mentioning here.

On the plus side, ARB have incorporated a feature which should be a no-brainer on every underbody protection system. They’ve recessed the bolt heads in the areas where you could be scraping or sliding over obstacles.

There’s nothing worse than discovering you’ve either sheared off a bolthead or damaged it so badly you can’t get it undone. Thankfully ARB have solved this all-too-common problem, before it happens.

AFN 4x4 ACCESSORIES UNDERBODY PROTECTION

AFN 4x4 Accessories Underbody Protection

• Material: Aluminium
• Thickness: 6mm
• Typical Weight (indication only): 20kg
• No-drill: Yes

Find out more at AFN

AFN 4x4 Accessories are better known for their quality bullbars. However, it also provides a wide range of underbody protection kits.

AFN is a European company, with years of experience in providing vehicle protection for military and United Nations’ vehicles. The Australian division feeds back information to its European engineering department, which designs all components in-house.

The kits are made from 6mm thick aluminium, meaning no issues with rusting. They come supplied with plenty of ventilation slots to keep your driveline cool. Typically, a full kit will weigh around 20kg.

ROADSAFE 4WD PROTECTION PLATES

Roadsafe 4WD Protection Plates

• Material: Aluminium
• Thickness: 6mm
• Typical Weight (indication only): 20kg
• No-drill: Yes

Find out more at Roadsafe

Roadsafe makes its underbody protection kits from 3mm-thick mild steel. It zinc plates them for protection against corrosion, meaning you can easily paint them if desired.

Where possible, Roadsafe allows access to oil filters and drain plugs without needing to remove the plates. Also provided are plenty of ventilation holes and points for water to drain away from inside the plates. Roadsafe also provides any bolts and nuts needed for installation.

While the zinc plating is a smart idea, it is only a surface coating. So once the zinc plating gets rubbed or scratched off, the bare metal underneath will be exposed to the elements.

These kits are comparatively heavy, typically around 40kg for a full protection kit.

RIVAL UNDERBODY PROTECTION

Rival Underbody Protection

• Material: Alloy, powder-coated
• Thickness: 6mm
• Typical Weight (indication only): 30kg
• No-drill: Yes
  

Find out more

Rival has taken a different approach with its underbody protections kits. It uses a lightweight alloy rather than stainless steel, mild steel, or aluminium.

The beauty of alloy is it can be pressed, meaning Rival can incorporate strengthening ribs in the plates, without the need for additional welded or folded sections. And being lightweight, Rival uses a 6mm alloy for maximum strength.

The other benefit of alloy is it won’t rust. So even if you damage the painted surface, the underlying alloy won’t be affected by corrosion.

These kits come with isolation rubbers, meaning no more squeaky aftermarket bash plates. And they supply all the fasteners you need for installation.

How We Review Products

4X4 Australia has been reviewing four-wheel drive vehicles and aftermarket products for more than 40 years.

When looking for the best underbody protection kits in Australia, there are some things essential to making sure you have the best off-roading experience.

When we compared each of the products in the list with others out there, we looked at:

• What material they’re made from
• Corrosion resistance
• What coatings they use
• Whether the mounting bolts are protected or exposed to damage
• Overall weight
• Strength, and
• Ease of installation

to determine what's the best product across each price point.

We also looked at user reviews and our own experience with these products to make sure our recommendations are for the best on the market.

Disclosure: When you buy through our links, we may earn a commission. We also include products that we do not earn a commission from.

Buyer’s Guide for Underbody Protection Kits

Most modern 4WDs are fitted with independent front suspension (IFS). This is a big improvement over the old-style front live axles, with better handling and ride.

However, it comes at a price.

Ground clearance under a vehicle with IFS is usually less than an equivalent live axle set-up. So protecting your radiator, steering components, sump and so on is more important than ever. Unfortunately, most new vehicles are supplied from factory with flimsy sheet metal or even plastic underbody guards.

A quality underbody protection kit (or bash plates) is pretty much an essential item if you’re planning on doing any serious 4WDing. It only takes one rock or to bottom out over a washout and you could be up for expensive repairs.

The aftermarket industry has recognised the need for decent underbody protection and provides a wide variety of options for you to choose from. We’ll take you through what to look for and how to select the best protection for your 4WD.

What to Look For

The first thing you need to consider is what type of 4WDing you’ll be doing. Aluminium guards are okay if you’re looking for peace of mind for general touring. However, you really can’t go past steel guards if you’re more in to tackling tougher tracks.

And if you’re planning on doing extended remote trips, mild steel is undoubtably the best option. Why? Well if the worst happens and you damage a bash plate, it’s a lot easier to bush panel-beat a steel plate back in to shape than an aluminium one. Aluminium tends to crack when you take to it with a large hammer!

The other consideration is welding. You’re far more likely to find a bush mechanic who can weld mild steel. But you’ll be lucky to find anyone who can weld aluminium or stainless steel … or to find someone with suitable welding gear.

Once you’ve decided on the right material, take a look at the finish. Zinc plating might look great when it’s new. But it’s easily scratched, which exposes the underlying steel to corrosion.

Powder-coating is tougher than zinc plating, but it tends to chip easily. After a few trips on gravel roads, your shiny new bash plates will likely be pockmarked with stone chips.

Many people shy away from stainless steel, as it has a reputation for cracking. This is true to a point … stainless steel is definitely more brittle than mild steel or aluminium. However, if the manufacturer knows its stuff, it’ll understand the tricks to avoiding creating weak points.

Look for long radius bends where the plate has been folded and radiused corners. These are indicators that the manufacturer knows its stuff.

If you’re concerned with looks, you can easily polish stainless steel and aluminium plates back to new condition. A liberal dose of WD-40 and a kitchen scourer pad under a random orbital sander, will have them looking like new in no time.

In contrast, painted, electro-plated or powder-coated surfaces aren’t so easy to bring back to as-new condition.

You’ve decided which material is best for your needs. Now we’ll let you in on a little secret …

Hide Those Bolts!

If you do a lot of 4WDing, sooner or later you’re going to bottom out on something. Hopefully your brand-new underbody protection kit will do its job and your vehicle sails through unscathed.

All good … until you need to take one of the plates off. That’s when you discover a bolt head has sheared off, or it’s completely mangled.

This is about the time when you wish your bash plates had recessed bolt heads.

Not many manufacturers do this … only KAON, TJM and ARB tick this box in our round-up of suppliers. TJM uses domed shrouds to protect the bolt heads instead of recessing them – a clever solution.

So if you want to spare yourself a lot of pain down the track, look for underbody protection kits with this feature.

Keeping Your Cool

Some of us have our own workshops or a mate with one. If so, it’s tempting to make your own underbody protection kit. And that’s fine, I’ve done this too – 3mm-thick stainless steel, laser cut and folded – perfect!

If you do decide to make your own, consider airflow around the engine sump, intercooler, radiator, gearbox and transfer case. Getting the airflow right can be tricky … and getting it wrong can be disastrous.

It’s easy enough to copy the manufacturer’s original bash plates. But if you make additional guards (gearbox and transfer case guards for example), you’ll be starting from scratch. Make sure there’s plenty of openings for adequate airflow – and that you don’t create places for mud and stones to build up.

Often, it’s easier and cheaper in the long run to go out and buy a ready-made kit. The manufacturers will have been through the learning curve already.

Does Weight Matter?

In our round-up, we included a typical weight for each underbody protection kit. It was intended as an indication only, so you could compare the various kits.

The heaviest kit is ‘only’ around 50kg, less than one person. Is weight even a consideration?

Yes, weight always matters. It’s so easy to keep adding weight as you add each accessory. Dual-cab utes tend to be front-heavy, so think carefully before throwing on the steel bullbar, winch and heavy-duty underbody protection kit.

Price

We didn’t list pricing in our reviews because there are too many variables. Some manufacturers sell a complete kit, some sell each bash plate individually, some offer options like diff guards.

Price varies widely. The kits we reviewed ranged from around $500 to nearly $1200. Ouch!

Consider your needs before forking out for the flashest brand-name underbody kit. You might find one of the cheaper options is more suited to your needs. In the process, you could save a whole lot of coin.

Speaking of money, underbody protection kits are cheap insurance in the long run. Spend a little now and you’ll potentially save big money in repairs somewhere down the track.