HDC - Hill Descent Control - The truck is equipped with Hill Descent Control (HDC) for tricky downhill runs. Exclusive to Land Rover, HDC supplements engine braking when low range is operational by monitoring wheel speed and applying the brakes to keep the vehicle from descending too rapidly when idling down steep or slippery slopes. HDC's job is to keep the Discovery moving at less than 4.4 mph when first or second gear is selected, or 7 mph in third and fourth.Phlawed said:
ACE - The most significant improvement to the Discovery Series II, in our opinion, is the availability of Active Cornering Enhancement (ACE). The old Disco regularly threatened to turn turtle in tight corners and rocked on its moorings in stiff crosswinds. The amount of body lean was ridiculous. Combined with numb, slow steering, the old model simply made no sense as an urban commuter. But ACE, a hydraulic system designed to counteract lateral body movement, solves this problem completely. ACE measures lateral acceleration during cornering and applies torque to the body to prevent roll.
I got this info off the net. BTW, if you have airbags in the rear (and not springs) be careful about putting your Disco on a lift.