Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Active On Demand Coupling (AOC)
Active On demand Coupling (AOC) and its Differential electronic module (DEM), has as its most important function to control the function for four-wheel drive, that is, power distribution between front and rear axle.
The system consists of an integrated clutch with a mechanical, a hydraulic, and an electronic part.
The clutch unit is located on the rear axle, between the final drive and the propeller shaft. The mechanical part is driven by the propeller shaft. The hydraulic part is driven by an electric pump.
Active On demand Coupling (AOC) generation 4 enables the following characteristics:
- Continuous control of four wheel drive, with electronic control of torque transfer.
- Rapid reactions
- No opposing forces when maneuvering or parking.
- Improved stability.
- Reduction of oversteering/understeering.
- Permanent capacity for four-wheel drive.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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