
Soaking car tires in water for a day or even a shorter period has no impact. However, if the tires are submerged in water for an extended period or the vehicle is parked in standing water that covers the wheel hubs, it can significantly affect the wheel hubs and brake components. Here are some rainy-day parking tips: Watch for standing water: When parking, always pay attention to standing water on the ground and avoid parking in such areas if possible. If you must park in a waterlogged spot, do not leave the vehicle there for too long. Water ingress measures: If the brake system gets wet, do not park immediately. Instead, drive a short distance while frequently applying the brakes to generate heat, which helps evaporate the water before parking.









I've worked in auto repair shops for most of my life and have seen too many water-soaked tires. If it's just going through a small puddle or being submerged for half an hour, there's usually no big problem. But if the tire is soaked in rainwater for a whole day, water can seep into the gap between the tire and the rim. Especially if soaked in saltwater, the aluminum alloy rims are prone to corrosion. Once when I was inspecting a tire for a car owner, after three days of water immersion, I peeled back the tire and saw rust spots on the steel belts. Such tires are particularly prone to bulging when driven at high speeds. It's best to avoid waterlogged areas when driving in the rain, and if the car does get soaked, be sure to check the rim seams.

Our materials laboratory has conducted specialized research on the degradation effects of tire water immersion. The molecular chains of synthetic rubber in ordinary tires can be broken down by hydrolysis, particularly when soaked in warm water above 40°C, where the molecular chain scission rate accelerates significantly. The steel belts inside tires begin to form rust crystals within 72 hours when exposed to oxygen-rich rainwater. The most hazardous scenario occurs on winter roads treated with de-icing agents—tires soaked in calcium chloride meltwater for 48 hours experience approximately a 15% reduction in tear resistance. Given that modern electric vehicles are heavier, they are more sensitive to tire wear. We recommend avoiding driving during heavy rainstorms whenever possible.

Last typhoon season, my car was submerged in the underground garage for two whole days. When I retrieved it, the tires looked fine, but I noticed the steering wheel shaking while driving. The mechanic said water had gotten inside the tires causing imbalance, and it took several days to drain them completely. Later, when driving at 120 km/h on the highway, the tire pressure warning kept going off, and I discovered the valve core's sealing ring had deformed. Now during rainy seasons, I'm extra cautious about water depth and would rather take a detour than risk it. After tires get waterlogged, it's recommended to do a dynamic balance check. Such hidden dangers only reveal themselves at highway speeds, which can be dangerous by then.

The structure of a tire is like a layered cake, and prolonged soaking in water can cause moisture to seep between its various structural layers. Soaking in clean tap water for a week mainly accelerates the aging of the tread rubber. However, soaking in street puddles is more problematic, as the water may contain oil stains or chemical agents, which can dissolve the protective wax layer on the tire sidewalls. Last time, a testing station found a car that had been submerged in floodwater for a month—the steel wires inside its tires had all rusted and broken, leaving them hollow. After a tire has been soaked in water, it must be thoroughly dried, with special attention paid to the area where the tire bead meets the wheel rim. During the rainy season, avoid parking in low-lying areas; it's best to choose a parking lot with elevated ground.

I dread rainy days the most when running long-distance transportation, as the hidden dangers of tires soaking in water create a chain reaction. If heavy truck tires are submerged in rainwater for more than six hours, the plasticizers in the rubber will leach out, causing the tread to harden and develop fine cracks. If left soaking further, water seeping into these cracks can corrode the steel belts. Continuing to drive under load at this point may lead to sudden steel belt fractures, resulting in tread blowouts. The worst incident I encountered was a customer who didn’t inspect their water-soaked tires, leading to the entire tread peeling off on the highway three months later. Now, I always keep a tire pressure monitoring system and rubber conditioner in my truck, applying the latter immediately after water exposure for protection. I recommend passenger car users perform deep tire every quarter.


