Loaded Minibus on the Grand Etang Descent
You are asked to drive a 14-seat minibus from the Grand Etang area down to Grenville. Twelve passengers and their shopping are on board, and there is a loaded roof rack. Before setting off you notice three things: the parking brake lever pulls up almost to the end of its travel with very little resistance; the brake fluid reservoir is at the MIN mark; and the near-side rear tyre has a bulge in the sidewall with a cut across it. The steering feels normal. The first kilometre of the descent is steep, winding and damp, with a low wall on one side and a drop on the other. About halfway down, after you have used the footbrake through a series of bends, the pedal starts to travel further before it bites, and the van begins to pick up speed.
1. The passengers are already seated and you are running late. Should you drive? Justify your answer against each defect you found.
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No. Each defect is a reason to stop on its own, and together they leave you with no reserve. The parking brake is your backup if the footbrake fails and your means of holding the van on a gradient; a lever that pulls to the end of its travel is out of adjustment and will hold very little with twelve people and a roof rack on board. Brake fluid at MIN means a leak, badly worn pads, or both, and fluid loss on a long descent is exactly how a pedal ends up on the floor. A bulge with a cut in a rear sidewall is a tyre that can fail without warning, and a loaded van on a hot, winding descent is the worst possible place for that to happen. The pre-driving check is your legal and personal responsibility; unloading, fixing the defects or finding another vehicle is the only defensible choice. The roof load also raises the centre of gravity, which amplifies every other problem.
2. The pedal is going long and the van is speeding up on the descent. Explain what is happening and set out your actions in order.
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The brakes are fading. Continuous dragging through the bends has overheated the pads and discs and can boil the fluid, so the pedal travels further and bites lower down. Act immediately. Select a lower gear, second or even first if the speed allows, and let the clutch out smoothly so engine braking holds the van back without locking the rear wheels. Keep firm, steady pressure on the pedal rather than pumping it repeatedly, and use the handbrake progressively if the pedal goes soft, remembering it is weak. Switch on the hazard lights and sound the horn on blind bends to warn others. Look for an escape: a wide verge, a lay-by, an uphill side road, anything that will stop you without a drop. Do not switch the engine off, because you lose engine braking and possibly power steering. Keep the passengers calm and braced.
3. How should the descent have been driven from the top?
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Before the descent begins, select a low gear, the same gear you would need to climb the hill, and stay in it so that engine braking does most of the work. Brake in short, firm applications to shed speed before a bend, then release, rather than riding the pedal all the way down; that lets the brakes cool between applications. Keep the speed well below the point where the bends surprise you, and keep left. Never coast in neutral or with the clutch down, and never rely on the handbrake for normal slowing. Leave a bigger gap ahead because the van is heavy, check the mirrors for traffic bunching behind, and if you smell hot brakes or the pedal feel changes, stop somewhere safe and let everything cool. On a wet road, every one of these margins should be doubled.