4×4 Suspension Accessories



At N1 4X4 we specialise in Dobinson 4X4 suspension accessories for Toyota 4WD vehicles. The Australian brand has over the past six decades gained an exceptional reputation as a supplier of highly robust products, which is why we always make sure we stock a wide range of Toyota 4X4 parts in our 3000 m² warehouse.

Coil Springs

Dobinsons Spring and Suspension™ proudly manufacture the highest quality replacement coil springs for many different applications to ISO9001:2008 international quality standards from their state of the art manufacturing facility in Central Queensland, Australia.

Dobinsons™ proudly boast one of the world’s largest ranges of coil springs including raised height and heavy duty 4wd springs, lowered performance passenger car springs, O.E. replacement springs and heavy duty springs for commercial vehicles.

As Dobinsons™ coil springs are manufactured in house, Dobinsons™ can manufacture smaller quantities and in most cases there are many different coil spring options available for your vehicle. This ensures the customer receives the best spring to suit their application and avoids a “One Size Fits All” scenario, especially important when selecting the correct spring rates and ride heights. When matched with a set of corresponding Dobinsons™ Heavy Duty Gas Shock Absorbers, Dobinsons™ can provide you with unrivalled performance and handling.

Start of the Art Heat Treatment
Heat treatment is unseen and is the most important steps in the coil spring manufacturing process. Hardening and tempering is completed by an extremely precise electronically controlled furnace to eliminate breakage and sagging.

Formed On Precision Mandrels
Each coil is precisely placed by a programmable logic computer to achieve perfect pitch. This is especially important in manufacturing variable and progressive rate springs.

High Intensity Shot Peening
All Dobinsons coils are shot peened to give longer life.

Precise End Configurations
Engineered coil ends are designed to fit directly into the original vehicle mounting points without any modification.

Design Technology
Spring Design engineers within Dobinsons Spring & Suspension™ utilize the latest coil spring design programs to ensure each spring will meet and exceed the design requirements and achieve the maximum working life. These state of the art design programs are crucial when designing variable/progressive rate springs to ensure laden and unladen spring rates are correct to provide the best possible ride comfort and handling.

Powder Coat Finish
A durable powder-coat finish provides extreme protection against the elements.

Fully Scragged & Load Tested
All coils are scragged 100% to eliminate subsequent spring sag and load tested to ensure that they meet and maintain the required specifications. Dobinsons also perform spring fatigue testing and spring hardness testing using in-house state of the art testing equipment.


4×4 U-bolts are made from high quality, 10.9 grade high tensile steel and  supplied with hardened deep nuts for maximum clamping pressure and reliability. It is recommended that when replacing leaf springs that new u-bolts are fitted. Supplied in anti corrosion zinc finish.

Polyurethane Bushes

Spring and Suspension’s polyurethane bushes have been designed and manufactured from the highest quality raw materials and unlike other competitors have been designed to suit both leaf springs and the original vehicle leaf springs.

Polyurethane leaf spring bushes provide a smooth comfortable ride and when combined with 4WD greasable shackles provide a far superior service life than the original vehicle bushes. Polyurethane bushes feature unique internal diamond grease traps to maximize bush and shackle life.

Steering Dampers

Spring and Suspension’s range of 4WD steering dampers are the perfect addition to your suspension kit. Featuring a larger body size for smoother cooler operation and 50/50 valving heavy duty steering dampers ensure comfortable controlled steering operation, especially on vehicles fitted with raised suspension, additional accessories or larger tires. Heavy duty steering dampers feature a massive 18mm chromed rod, 32mm bore and 50mm body with steel stone guard. End mountings are kept the same as the original vehicle mountings to ensure quick hassle free fitment.

Leaf Springs

With over 60 years of experience manufacturing in Australia, Dobinsons Spring and Suspension are no strangers to providing only the highest quality spring and suspension components, and Dobinsons range of leaf springs are no exception. Dobinsons range of leaf springs include raised and heavy duty leaf springs for 4wd’s, heavy duty and parabolic replacement springs for trucks and commercial vehicles and raised and replacement springs for 4×2 utilities and passenger vehicles. In most cases there are multiple options available to ensure the correct spring is available to meet each customer’s requirements. Manufactured to international quality standards ISO9001:2008 and TS 16949 using premium grade Sup 9 silicon manganese spring steel, Dobinsons range of leaf springs are made to world leading quality standards.

Dobinsons leaf springs are manufactured from only the highest quality raw materials. With over 60 years of experience Dobinsons understand the importance of selecting not only the highest quality spring steel but the correct grade that will give the longest life under the harshest conditions.

Dobinsons design engineers ensure that every spring is designed specifically for the vehicle, load and height requirements for each application. The spring design is the most important step in manufacturing a leaf spring and with over 60 years designing and manufacturing, Dobinsons understand the importance of this. Design features include Drawn, tapered and thinned leaf ends for even stress distribution over the entire spring pack, 2 stage spring design for the rear of most vehicles to achieve optimum ride and handling both laden and unladen and carefully selected leaf lengths and thickness’s to maximize the spring life, comfort, load carrying capacity, wheel travel and performance.

Each step of the manufacturing process of Dobinsons leaf springs is vital to ensure the complete spring pack will outperform the competitors. Each spring is manufactured to international quality standards ISO9001:208 and TS 16949.

For most vehicles Dobinsons offer multiple options to best suit the customers need. This ensures the correct spring rate is matched for the vehicle and accessories added, and provides a raised height where applicable without going beyond the safe design requirements to enhance performance, load carrying capacity and off-road ability without compromising safety.

Where possible Dobinsons leaf springs utilize full military wrappers and full length wrappers to provide additional support to the main leaf and improve safety.

Anti-Friction inter leaf liners are used to reduce the friction at each leaf end where the load is greatest and provides a smoother, quieter ride.

Dobinsons leaf springs feature high strength alignment clips with nylon insulators to reduce wear and noise. Nyloc nuts are also featured on bolted clips to prevent loosening off nuts which can cause tyre damage.

Each Dobinsons leaf spring is shot peened on the tension side of each life and completely scragged. This dramatically reduces the chance of sagging and breakage and doubles the expected working life of the spring. Random sampling from production is then also durability tested to ensure Dobinsons leaf springs will outlast the competitors.

Designed, developed and tested in Australia by Dobinsons in house suspension design engineers Dobinsons 4X4 shock absorbers are designed and tested for the harshest conditions right across the world.

As Dobinsons Spring and Suspension export to over 40 countries worldwide from their Australian head office, the importance of quality is at the forefront in the complete design and manufacture process. This ensures every shock can withstand the blistering heat and corrugations of the Australian outback right through to the subzero temperatures of a Siberian winter.

Dobinsons 4×4 shock absorbers are a Twin Tube Nitrogen Gas charged shock absorber made from the world’s highest quality external and internal parts sourced from all parts of the world. Dobinsons shock absorbers utilize an 18mm chrome piston rod and 35mm bore for most vehicles, and a 32mm bore where space requirements do not allow this.

Unlike some other brands, each Dobinsons shock absorber is designed specifically for the vehicle and application and is designed to perform best when matched with Dobinsons Coil Springs. In some cases multiple options are available to ensure the best possible ride, handling and comfort is achieved for the complete suspension system.

Nitrogen Gas Charged

Each shock absorber is filled with high quality German Fuchs shock absorber oil then filled with low pressure nitrogen gas to pressurize the oil and assists in reducing oil aeration commonly known as Shock fade.

Superior Design

Where possible Dobinsons design each part number to provide a longer shock absorber for more wheel travel, firmer valving for a more controlled ride and a larger body with increased oil capacity for cooler operation than the original vehicle shock absorbers.

Other hidden design features also include thicker external tube wall thickness up to 3mm on Dobinsons 4×4 struts where other brands use as small as 1.5mm
Selected Dobinsons 4×4 struts also include single piece drop forged lower mounting stems to provide far superior strength and reliability.

High Quality Parts

Only the highest quality internal and external parts are used to ensure hassle free long life operation. When developing shock absorbers, Dobinsons test every single component of the shock absorber to ensure each part can with stand the vast difference in operating temperatures, the vast difference in environment and conditions and ensure each part provides long service life. These include Japanese NOK Multi-lip seals, Fuchs German Shock absorber Oil, Natural Rubber bushings for reduced Noise Vibration Harshness,  high quality Teflon piston rings and Double chrome hardened rods are just a few of the components that put Dobinsons shock absorbers head and shoulders above the rest.

Manufacturing Process

As Dobinsons Spring and Suspension have been manufacturing the highest quality springs and suspension components for over 60 years; they are no strangers to state of the art manufacturing processes. Dobinsons 4X4 shock absorbers are manufactured using the latest technology and are manufactured to TS16949 International Quality Assurance Systems. This includes double re-enforced robotic welding, Friction welding, CNC Machined components and drop forging of high stress mounting components.

Testing Process

Dobinsons 4X4 shock absorbers are first completely quality checked and Valve Force-Velocity Dyno tested in the factory before final approval.
Dobinsons then perform further in depth quality testing in their Australian head office to ensure long life reliability.

  • In house Dyno Testing – Dobinsons perform further sample testing of the shock absorber valve forces using a state of the art Dyno testing machine. This ensures each shock absorbers is manufactured in accordance with Dobinsons requirements to provide accurate valving for each application
  • In house Durability testing – A completely custom made shock absorber durability tester was built for Dobinsons to simulate extreme conditions a 4wd experiences over its life time. This machine is crucial when designing and testing each component to minimize any possibility of component failure. The durability tester simulates real life conditions with varying velocity’s where shock absorber operating temperatures can exceed staggering temperatures of over 100 degrees Celsius. The tester provides real time feedback of temperatures, velocity and valve force which is crucial when testing for shock fade when Dobinsons shock absorbers are pushed beyond a few million cycles
  • Component and Performance testing – Dobinsons shock absorbers are also stripped down and components tested using different process to ensure they meet Dobinsons strict quality requirements. Finally ride quality and in vehicle performance testing is performed to check final ride comfort, handling, load handling ability and performance to ensure each type of shock absorbers outperforms the best.

Dobinsons Spring and Suspension’s range of heavy duty 4WD torsion bars are manufactured from high quality micro alloy steel with a thicker bar diameter than the original vehicle torsion bars to improve performance when accessories are fitted. When vehicles are fitted with additional accessories such as steel bullbars, winches, dual battery kits and other frontal accessories the weight placed on the torsion bars can be dramatically increased.

The torsion bars fitted to the vehicle will not withstand the additional weight placed on the vehicle and will be prone to sag and will offer poor handling and offroad performance. Dobinsons heavy duty 4wd torsion bars feature increased spring rate (thicker bar diameter) to better handle the additional weight and provide far improved handling, ride height and offroad performance.

Increased Spring Rate

Dobinsons torsion bars feature an increased bar diameter, thicker than the original vehicle torsion bars. Dobinsons uprated torsion bars provided a far superior ride that will greatly reduce bottoming of the suspension and will improve the vehicles handling whilst also offering far greater reliability at increased ride heights.

Cold Rolled Splines

Dobinsons torsion bars feature cold rolled splines to increase strength, reliability and ensure a perfect fit.

Durable Powdercoat Finish

A thick durable powdercoat provides protection against corrosion.

Directionally Preset and Scragged

As torsion bars have load applied in a particular direction during compression travel, Dobinsons have their torsion bars directionally preset and scragged to prevent sagging and breakage.

Simple fitment

Dobinsons heavy duty torsion bars have precision end fitment and are marked both left and right hand side, and also importantly front and rear to ensure correct simple fitment the first time. Fitting torsion bars on the incorrect side or back to front will damage the torsion bars as they are preset and scragged in the required direction.

Shackles & Pins

Spring and Suspension’s range of 4WD shackles and pins offer have been designed and manufactured to maximize the life of both the polyurethane bushes and shackles. Incorporating a recessed twin hole greasable design the ensure both halves of the polyurethane bush receive even grease distribution. Greasing polyurethane bushes not only reduces friction and wear, it also reduces the chances of corrosion on the shackle pins and reduces squeaking. 4WD shackles and pins are a heavy duty design and provide simple servicing through external grease nipples.

In some cases we also provide anti-inverse shackles to prevent the shackles from inverting on lifted leaf spring vehicles.

Shackle Types

Pin Types

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