Dunn & Watson Pty Ltd supply a large range of automotive water tanks for caravans utes and 4×4. These vehicle water tanks can simply be bolted underneath your ute tray, truck tray or trailer underside. They are available in 15, 23, 30 and 60 Litre models and feature a hand pump ideal for soap or sunscreen. When we look at introducing a new line of automotive water tanks, we examine the quality, applications and the full range existing in both Australia and global markets.

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Caravan/Ute/4x4 Water Tanks - 4WD Water Tanks – Automotive/Ute Tray Water Tanks

4WD Water Tanks - Automotive/Ute Tray Water Tanks

Dunn & Watson currently provide 4WD water tanks ranging from 15L up to 75L that are ideal for your 4×4, Ute, caravan, RV or camper trailer. We have water tanks that should cover all your needs including tanks that fit over wheel arches, in front of headboards in the back of your Ute, trailer side board walls and under the tray of your vehicle.

Our 40L Tourer Tray Water Tank is particularly useful when you need to store extra water, but there’s not a lot of room under the tray, because you have already installed an under tray drawer unit. The Tourer tray is designed to fit this type of situation with dimensions of 455mm long x 690mm wide x 200mm deep.

Other great options for carrying extra water are the wheel arch 4WD water tanks, because they make use of a difficult space that would otherwise go to waste. Currently we stock 23L and 48L single wheel arch water tanks, as well as a large 75L dual wheel arch option for additional storage.

Two other popular space saving options are the Dunn & Watson 70L Canopy Headboard Tank and the 20L Side Board Water tank. These are often fitted to service trucks but are also great for campers and 4WD enthusiasts as they provide additional water that can be easily accessed and make the best use of the space. Some of our water tanks even have soap and sunscreen dispensers making life on the road very comfortable!

Caravan/Ute/4x4 Water Tanks - 4WD Water Tanks – Caravan/Camper Trailer Tank

4WD Water Tanks - Caravan/Camper Trailer Tank

Dunn & Watson currently provide 4WD water tanks designed for installation under your vehicle in volumes ranging from 65L, 80L, 100L and 140L. These roto moulded water tanks are built for Australian conditions and are trusted by some of Australia’s largest caravan and camper trailer manufacturers. They are so tough that you don’t need to install straps or bash plates to protect them from accidental damage or punctures caused by coming into contact with rocks or chips on the road.

Built at our Brisbane factory, the tough poly walls of these water tanks normally fluctuate between 5mm to 8mm thick prior to installation. Depending on the environmental temperatures, the thickness of these walls can vary between 9mm to 12mm once installed, providing all the on road protection you need to travel off road for extended periods of time. They are perfect for 4WDs, camper trailers and caravans and the water is potable.

All these 4WD water tanks come with a fill up and overflow hole on the front of the tank and a drainage hole at the rear. The rear drainage hole can be used to attach a second tank or to simply drain the water. Once installed, all you need to add is a water pump for easy access to the water, not forgetting a lockable water filter cap for additional security.

The dimensions of the 65L tank are 810mm long x 610mm wide x 200mm deep; 80L tank is 810mm long x 610mm wide x 250mm deep; 100L tank is 1200mm long x 700mm wide x 180mm deep; 140L tank is 1500mm long x 700mm wide x 180mm deep.

Caravan/Ute/4x4 Water Tanks - Diesel Tanks

Diesel Tanks

Dunn & Watson currently provide a range of diesel tanks ranging from 40L, 48L, 65L and 75L. These roto moulded diesel tanks are all manufactured in Australia using diesel grade polyethylene with tough 5mm to 8mm walls and are a distinctive yellow colour to differentiate them from 4WD water tanks. These diesel tanks have a similar profile to many of our water tanks but come with heavy duty brass fittings and are stamped with a tag that indicates they are used for diesel only.

Our 40L Ute tray diesel tank is 455mm long x 690mm wide x 200mm deep and is designed to fit underneath the Ute tray. The 48L wheel arch diesel tank is 1300mm long x 170mm wide x 380m deep and as its name implies, is designed to fit in the wheel arch of your 4WD vehicle. The 65L trailer diesel tank is 810mm long x 610mm wide x 200mm deep and is designed to fit underneath a trailer or camper trailer. The 75L dual wheel arch diesel tank is 1340mm long x 200mm wide x 400mm deep.

These diesel tanks are perfect for carrying additional fuel on extended trips or when you are travelling through areas where fuel stops are few and far between.

Caravan/Ute/4x4 Water Tanks - Caravan Grey Water Tanks

Caravan Grey Water Tanks

Dunn & Watson currently provide a range of caravan grey water tanks ranging from 65L, 80L and 100L. They are actually coloured grey to distinguish them from our blackwater 4WD water tanks and our yellow diesel tanks. Our Australian made grey water tanks are perfect for caravans, camper trailers and RV motorhomes. They are designed with tough 8mm thick walls, so you don’t need any straps or basher plates to prevent punctures on the road.

The outlet and inlet pipes come with a wider bore than the potable water tanks to better suit your needs on the road (1 ¼ inch fittings). Installation is easy because all you need to do is bolt the tank to the underside of your vehicle using the pre-drilled holes.

Installing a waste water tank in your caravan, camper trailer or RV is good for the environment as the tank collects all the domestic wastewater (except from the toilet). This includes wastewater from the kitchen and bathroom sinks, showers and washing machine. Many Australian campsites require RVs and caravans to store their grey water and dispose of it in specially built dump sites, whilst others are happy for it to drain into the ground. It’s best to ask about these rules regarding disposal of grey water at the site office.


Caravan/Ute/4x4 Water Tanks - Water Tank Accessories

Water Tank Accessories

If you’re fitting 4WD water tanks to your vehicle then you most probably need a few accessories. Dunn & Watson provides a range of these accessories so you can get the most out of your water tanks. One of our more popular accessories is the SeaFlo 12V portable washdown pump kit that makes washing your 4WD, caravan or trailer a very quick and easy process. With this accessory you don’t even need your own water supply, because you can either fill a bucket from your tank or from a local creek and clean off the mud and sand before hitting the road.

We also have a PVC hand pump that can be used instead of a tap to access water from your 4WD water tanks. It’s a good idea to always have one of these stored away on your trip, just in case it’s needed in an emergency. We also have key lockable filler caps that make sure that the water isn’t accessible to anyone else during your trip. These are often fitted to tanks on camper trailers and caravans.

If you want to step it up a notch then check out our portable shower water heater box that’s ideal for lovers of hot showers. This box provides a protective cover for your existing water heater and can be installed in your canopy, 4WD or camper trailer. It’s made from tough aluminium, but is still very lightweight, and comes with over centre fasteners and a rubber weather seal.

Other accessories include a SeaFlo RV Supreme 12V water pump that’s designed for caravan and RV pressurised water systems. It’s a compact and quiet unit that can be configured with different inlet types. Lastly, we have a stainless steel water tank filler and breather plate that provides an easy access point for the water tank installed in your 4WD Ute tray.