Coil Conversions

One of the most popular choices for a touring or work vehicle is the Toyota Landcruiser due to it’s proven reliability, simplicity and ruggedness.

The 70 series Landcruiser is a common choice thanks to plenty of practical storage and a large payload when setup correctly. One of the biggest complaints from 70 series owners is the lack of ride comfort.

Wagon variants of the Toyota Landcruiser such as the 80, 105 & 200 series are also popular touring vehicles due to their comfortable coil sprung suspension and off-road ability. The biggest downfall of these wagons is the lack of storage space and available payload.

When fitted with a coil conversion the 70 series Landcruiser is the perfect combination. It becomes a vehicle with reliable running gear, plenty of storage, a large payload, corrected wheel track & now the comfort of coil sprung rear suspension.

This modification can be installed on the whole range of 70 series Landcruiser’s from 2007 onwards including the 76 series wagon, 78 series troopy, 79 series single cab & 79 series dual cab.

Coil Conversion Kits And Packages

Jmacx bolt in coil conversions can be purchased as a basic coil conversion kit or in a full package to increase the gross vehicle mass (GVM).

The basic coil conversion kit puts together the bare components to convert the rear of a 70 series Landcruiser from leaf springs to coil springs, this allows you to add your own suspension components for a custom install. Our full packages come as a complete vehicle solution for the coil conversion including all suspension components, a brake upgrade and an exhaust system. With the appropriate engineering the full packages offer many benefits including increased GVM, maintained or increased towing capacity, legal suspension lift and legal fitment of bigger tyres.

Our entry level full package is the 3900kg GVM package, this is the starting point for all coil conversion packages and you can upgrade the package if required. The coil conversions are fitted for a wide range of applications so the packages are customisable to suit your needs.

Below you will find a list of components included in the basic coil conversion kit, a list of inclusions in our standard 3900kg GVM package and a list of the optional extras & upgrades.

Basic Coil Conversion Kit

  • Bolt in coil conversion cradle
  • Fabricated 6mm diff housing
  • EN26 full floating rear axle kit
  • Adjustable upper control arms
  • Adjustable lower control arms
  • Rear adjustable sway bar & links
  • Rear adjustable panhard rod
Jmacx basic bolt in coil conversion kit to suit Landcruiser

Standard 3900KG Package

  • Basic coil conversion kit
  • 3900kg GVM upgrade
  • 2 inch suspension lift
  • 33 inch tyres (legally fitted)
  • Jmacx Pro series shocks
  • Front & rear coil springs
  • High pressure airbag kit
  • Castor correction bushes
  • Billet sway bar spacers
  • Upgraded brake booster
  • Torqit stainless exhaust
  • Workshop consumables
  • Installation & engineering

Optional Extras And Upgrades

  • 4200kg or 4495kg GVM
  • 3 or 4 inch suspension lift
  • 35 inch tyres (legally fitted)
  • King 2.5 remote res shocks
  • Jmacx billet radius arms
  • Heavy duty steering damper
  • Braided brake line kit
  • Adjustable speedo corrector
  • Heavy duty clutch upgrade
  • Brown Davis 185L fuel tank
  • 300mm chassis extension
  • Custom colour coding


The Jmacx bolt in coil conversion kits are a great option for daily drivers and general use vehicles. For serious tourers or heavily loaded work utes the next option is the Jmacx 4495 super chassis.

Instead of using a bolt in coil conversion cradle the Jmacx super chassis replaces the rear end of the factory Toyota chassis, this option incorporates a coil conversion and a 300mm chassis extension. The Jmacx super chassis features a 4495kg GVM and an increased towing capacity to 4000kg or 4500kg depending on transmission type.

For all applications that require a big payload or large towing capacity the Jmacx 4495 super chassis is well suited.

Frequently Asked Questions

A coil conversion is the process of removing the standard leaf spring suspension system from a vehicle and converting it to a coil spring suspension setup.

One of the biggest advantages of coil springs is ride comfort, coil springs are known for offering a plush ride whilst leaf springs traditionally ride rougher. Coil spring vehicles often handle nicer onroad and also perform better offroad due to increased ground clearance & wheel travel.

Our coil conversions aren’t a one size fits all modification and therefore there is not a set price for the conversion. There are a few different ways to do a coil conversion and there’s a lot of options for different parts to be included. Generally no two coil conversions will be the same price due to each individual customers preferences however pricing for a full vehicle package starts from around $20,000 including parts, installation & engineering.

We can engineer the coil conversion pre rego on brand new vehicles or post rego on already registered vehicles. Providing the vehicle gets engineered and all of the components within the kit remain on the vehicle once engineering is done then the modification will be 100% road legal.

All of our GVM packages and coil conversions can be engineered, once engineered they are completely road legal. Generally, if a modification is road legal and engineered your insurance company won’t have any issues covering your vehicle and the modifications. We do always recommend double checking with your insurance company just to be sure.

The Jmacx diff housing retains the use of a factory Toyota diff centre, diff lock, driveshaft, brakes, seals, bearings and hubs. Factory bushes are also used and the coil kit uses factory length suspension arms. The use of factory fitted items makes it much easier & quicker to source spare or replacement parts.

Yes, the Jmacx diff housing is a 6mm fabricated housing and is 100mm wider than the standard diff housing. This corrects the wheel track to match the width of the front axle. The Jmacx diff is also much stronger, standard diff housings are only rated to 2300kg, whereas the Jmacx diff housing is tested to 3000kg (the legal axle load rating will depend on the specific GVM kit).

There is the option to fit 33 or 35 inch tyres to a 70 series with a coil conversion and this is based on suspension lift. A 2 inch lift allows for the fitment of 33 inch tyres and 3 or 4 inch lifts allow for the fitment of either 33’s or 35’s.

To install a basic coil conversion, we will generally need your car for approximately one week. When the kits become more complex with alterations or optional extras this does add time to the installation process and we may need it for longer.

Yes, every vehicle requires load rated rims & tyres regardless of whether or not the GVM has been upgraded. To work out the required load rating for your rims & tyres you can simply divide the vehicles highest axle rating by half, usually this will be the rear axle. For example a 2020 model Landcruiser 79 series dual cab comes from Toyota with a 3300kg GVM, the front axle rating is 1480kg and the rear axle rating is 2300kg which means the minimum required load rating for rims & tyres on this vehicle is 1150kg each (2300kg divided by 2 = 1150kg).

Technically not, a GVM upgrade should never decrease your towing capacity however it may reduce the amount you can legally tow. Most GVM upgrades will only replace suspension components which allows your GVM to be increased but makes no change to your legal combined weight of GVM and towing capacity (often referred to as GCM). Jmacx coil conversion packages upgrade a lot more components and undergo extensive testing which allows you to legally utilise your full towing capacity while loaded at your full GVM.

Currently no, at this stage we only offer coil conversions for the 70 series Landcruiser range of vehicles. These kits have been developed specifically for the V8 models from 2007 onwards and do not fit older models.

Confused or keen to find out more?

We get it! There’s a lot to take in and you potentially now have more questions than answers.

That’s okay, our sales team will be more than happy to talk you through everything about coil conversions and help find the best option for you. We can put together a package and provide a personalised quote to best suit your individual application. Get the ball rolling by filling out our contact form.