GVM Upgrade Specifications

The JMACX GVM kit not only strengthens the diff but also the rear wheel hubs and bearings are upgraded to suit the increase in load carry capacity. The rear wheel bearing area and wheel bearing itself is the major issue. Extra engineering for SSM (Second Stage Manufacture) is included in the GVM upgrade. The premium suspension solution includes JMACX’s signature Alpha Shocks, high quality coils and high pressure in coil airbags providing 2 inches in the rear and levelling in the front.

Under testing the factory braking system was found inadequate for a GVM upgrade as it failed the braking test due to excessive heat which caused component failure. So this GVM upgrade includes JMACX Ram 1500DS brake upgrade as standard, with larger slotted rotors, 6 pot callipers, and high performance brake pads to reduce glazing and brake fade via heat dissipation, allowing the vehicle to carry more load safely. When fitting the ram wheels please note that they will need to be bored to the OEM factory size for the wheels to fit.

* Post Rego Lift, Tyres, BTC and GCM remain engineer and state dependant. Post rego vehicles with ESC are limited to 50mm of lift in all states

For more information on axle loads, BTC AND GVM please read our article here CALCULATE YOUR WEIGHT

All JMACX products have full engineering and are approved by all states in Australia for post rego vehicles to ensure you are safe and legal on Australian roads. To see what comes in your JMACX Ram 1500 DS 4200 GVM upgrade please watch the video and then use the kit builder above to get a quote today.

Frequently Asked Questions

Can I just apply the QLD 10% GVM upgrade by re-rating my axle?

No, you cannot exceed the manufacturer’s axle load rating under the QLD 10%.  You can increase your GVM in QLD by approximately 7% based on factory axle load ratings.

Can I just add bracing to the factory diff?

Bracing still leaves the diff with an inherent weakness as it stops at the backing plate and is well before the compromised bearing. Bracing the factory diff does not resolve the point of failure, but can increase the impact on the loading point of the bearing due to stiffening of that rear housing.  See below for failure example.

  Failure for RAM 1500 wheel bearing area

Can I get a GCM upgrade on my RAM 1500 DS?

JMACX will not provide a GCM increase in addition to your GVM increase on the RAM 1500DS due to excessive loading on the chassis.  There is plenty of evidence demonstrating this failure in the current market.

What import models and diff models does the GVM upgrade cover?

Note that the GVM upgrade so applies to 1500 Rams that were imported with the 3.9 Ratio diff housing (ASV Imported Vehicles). Other Vehicles have been imported with the 3.2 ratio diff centre.

DIFFERENTIAL OPTIONS

OPTION 1: MODIFIED DIFF HOUSING OPTION

The engineers at JMACX have developed a procedure of modifying the end of the tube, welding on a thicker tube axle and a full float bearing hub assembly. This allows for larger wheel bearings to cope with the additional axle load. Internally, the diff is strengthened by a full inner tube. Full floating bearings offer greater handling of larger loads. The JMACX diff upgrade increases the axle capacity to 2500kg.

OPTION 2: MODIFIED DIFF HOUSING OPTION PLUS NEW AIRLOCKER

In addition to the modified diff housing as above in option 1, with new fitted upgraded diff bearings, and new air locker.  ***Air locker availability TBC***

OPTION 3: NEW JMACX REPLACEMENT 9” DIFF HOUSING

The JMACX 9” diff option with air locker is the ultimate choice, as the strongest diff available. With bigger gear sets, upgraded parts and with the longest warranty. With a factory replacement diff close to $24,000, the 9” JMACX diff represents quality and value.

NON Optional Core Exchange

A deposit of $2000 will be required for core exchange. This deposit will be refundable depending on the condition of the differential when assessed by the JMACX HQ Differential Team. If the differential is deemed in sound rebuildable condition, a full deposit will be refunded. If additional parts are required only partial deposit will be refunded based on the cost of the repair parts. If the differential is damaged beyond repairable use then no deposit will be refunded. Diff sales without a core exchange (no diff available for exchange) can be only discussed with JMACX HQ.