Almost all new vehicles are fitted with disc brakes, but off-roaders are a quirky breed. How many of us are still driving around in old but faithful wagons that we wouldn’t part with because we know them inside-out and value their bombproof reliability? Quite a few. If you’re one of them, and your vehicle is old enough, it’s a good guess that one of the less reliable bits is the brake system.
It's also possible that your newer 4x4 will have a drum brake setup that acts when the handbrake is on. These are usually found acting on the inside of a disc brake setup on the rear wheels.