Welcome to Jmacx

JMACX is the innovator and industry leader when it comes to coil conversions and GVM upgrades for the ultimate Landcruiser. Giving you the strongest coil conversion on the market with unrivalled stability and handling.

GVM upgrades, with the highest axle load rating in Australia, allowing you to practically load and use the full potential of the GVM upgrade in your vehicle.

With hundreds of conversions done in commercial, military, outback tourers and work vehicles, with millions of combined kms driven in some of the worlds harshest condition, this kit has proven itself to go above and beyond. No wonder it is the worlds number one trusted coil conversion.

LC79 Series 5800 GVM 6×6 Coil Conversion

The Jmacx 5800 6X6 triple locked LC79 super chassis kit has taken the Landcruiser to a whole new level, giving you one of the highest GVM’s with a tow increase also to 4500kg and the best part is this is all done on coil suspension allowing the vehicle to still drive and ride like a dream.Here are some key points as to what you can get from a Jmacx track corrected coil conversion.

  • Jmacx 5800 super chassis coil conversion can be done *PRE AND POST REGO* in all states
  • Jmacx 5800 super chassis coil conversion can have up to 4inch of lift and 35inch tyres
  • Jmacx 5800 super chassis coil conversion has an integrated chassis stretch and bracing kit 
  • Integrated tow hitch and built in winch cradle.
  • with this Jmacx super chassis coil conversion you get a:
  • Increase GVM to 5800kg
  • Increase BTC to 4500kg
  • Increase GCM to 10300kg
  • Axles load rating to 3000kg each
  • Vehicle chassis length extended by 1000mm overall
  • SSM Number:49954(visit rcvs website to confirm specs)
  • (for more information on axle loads,BTC and GVM please read our article here CALCULATE YOUR WEIGHT)
All Jmacx products have full engineering to ensure you are safe and legal on Australian roads. To see what comes in your Jmacx bolt in coil conversion please watch the video and then use the kit builder bellow to get a quote today .


this system can be fitted at :

visit Australian expedition vehicles


visit Boss Aluminium

visit Swank Fabrication 

If you are a overseas customer please contact:

visit tough gear trading

Frequently Asked Questions


Is this a self installation kit ?

No, JMACX 6×6 will only Supply to a JMACX and Australian Patrol Vehicles (AEV) Approved workshop.


How Long is a JMACX ?

  • JMACX 79 Series 6×6
  • 6200mm (2400 Tray)
  • 6600mm (2800 Tray)


  • AEV/JMACX 200 Series 6×6
  • 7.2 Mtrs

What does a 6×6 Weigh ?

  • JMACX 6×6 79 Series
  • A JMACX 6×6 79 Series Weighs Appox 350kg Heavier than the factory Tare Weight.

  • AEV/JMACX 200 Series 6×6

  • Approx 2750kg

Can this be approved in all States ?

  • Yes, all States.

What is the Maximum Tyre & Lift Height Available ?

  • 4 inch Lift Max
  • 35 inch Tyres Max

Can I Have Lockers ?

  • Standard GXL comes with Factory Front & Rear Electric Lockers.
  • JMACX 6×6 System is supplied with a Locker


Is JMACX 6×6 Chassis Cut & Extended ?

  • No, JMACX Fabricate a Complete Chassis Section to Replace the existing rear assembly to increase chassis strength.

What is the Fuel Economy like ?

  • Two tests on comparable vehicles 6×6 and 4×4 with the same tyre size, similar tuning, similar towing weights & loaded up for touring The 6×6 was 1 litre per 100KS Heavier on Fuel Consumption.