The Challenge: Water, Gradients, and Grip
Driving in the hills during the monsoon presents a unique combination of risks. First, water on the road surface dramatically reduces the friction your tyres need to grip the tarmac. Second, the steep inclines and declines mean gravity is constantly working
against you, making it harder to stop and easier to lose control. Wet roads can increase your vehicle's stopping distance by a significant margin even with a perfectly healthy car. A layer of water acts as a lubricant between your brake pads and rotors, and between your tyre tread and the road. This reduction in friction is the primary reason why pre-trip checks of brakes and tyres move from routine maintenance to a critical safety procedure.
Brakes: Your First Line of Defence
When driving in rain, a film of water on the brake pads and rotors can cause a frightening delay in braking response. This is often felt as a 'spongy' or soft pedal. In hilly terrain, where you might use your brakes more frequently on descents, the components can heat up. If moisture has seeped into your brake lines—a common issue in humid monsoon weather—it can lower the boiling point of the brake fluid. This may lead to a dangerous condition called brake fade, where the brakes lose their stopping power almost entirely. Before you leave, check your brake fluid level and colour; it should be clear, not murky. Listen for any squealing or grinding noises when you brake, as this indicates worn-out pads that need immediate replacement.
Smarter Braking on Hill Roads
Your driving technique must adapt to the conditions. Instead of relying solely on your brakes during long descents, use engine braking by shifting to a lower gear. This helps control your speed without overheating the brakes. If you've driven through a puddle or a waterlogged patch, gently tap your brake pedal a few times on a clear stretch of road. This helps generate a bit of heat to dry off the rotors and pads, ensuring they are ready to perform when you really need them. Most importantly, double your following distance. The combination of wet roads and downhill slopes means you will need far more room to stop safely. Avoid sudden, hard braking, which can easily lock up your wheels and cause a skid.
Tyres: Your Only Connection to the Road
Your tyres perform a vital function in the rain: they channel water away from the contact patch—the small area that actually touches the road. The deep grooves in a tyre's tread are designed specifically for this purpose. When tyres are worn, the tread is too shallow to clear the water effectively. This can lead to a terrifying phenomenon called aquaplaning (or hydroplaning), where a layer of water builds up between the tyre and the road, causing you to lose all steering and braking control. At this point, your car is essentially floating. The risk of aquaplaning increases with speed and the amount of standing water.
The Essential Tyre Checklist
Before any trip to the hills, especially in monsoon, conduct these simple checks. First, inspect your tread depth. While a minimum of 2-3mm is often suggested, newer tyres offer the best performance. You can find tread wear indicator bars moulded into the grooves of your tyres; if the tread is flush with these bars, it's time for a replacement. Second, check your tyre pressure when the tyres are cold. The manufacturer's recommended pressure is usually on a sticker inside the driver's door jamb. Incorrect pressure compromises grip and can increase the risk of aquaplaning. Also, remember that air pressure changes with altitude and temperature, so a check before starting your return journey from the hills is also wise. Finally, look for any visible cracks, bulges, or uneven wear, as these can be signs of underlying problems that are exacerbated by tough road conditions.
