Is it okay to drive at high speeds for more than 12 hours?

[VonGrant]

No. If a vehicle is driven continuously for more than 12 hours, problems may arise: 1. Cooling system issues: When the vehicle operates at high speeds for an extended period, it may lead to cooling system failures, resulting in inadequate heat dissipation. For example, the radiator may become clogged, or other cooling system malfunctions may occur. This is especially true for larger vehicles with aging components, which may even experience cylinder scoring and engine damage. 2. Engine oil leakage: During prolonged driving, the engine operates at high speeds for an extended period, which is a severe test. This can lead to oil leakage, abnormal oil consumption, and in severe cases, may even cause the vehicle to catch fire. 3. Reduced engine output: If the vehicle is driven continuously for a long time, the exhaust temperature will rise sharply, potentially triggering the ECU's overheating protection. This will affect the engine's output capability, significantly reducing the vehicle's performance.

[VonWillow]

Driving for so long really requires caution. I once drove continuously for 10 hours on the highway, and my legs were numb when I got out of the car. Technically, it's possible to drive for over 12 hours at high speed, but it's strongly not recommended. The car's engine is under high load for a long time, causing the oil temperature to soar, which can easily lead to overheating and bearing failure over time. Tires are also a risk—continuous friction can cause abnormal increases in tire pressure and accelerated tread wear, leading to a potential blowout on the road. More importantly, the driver can't handle it. Traffic laws mandate a 20-minute break after 4 hours of driving. I've seen fatigued drivers drift out of their lanes without even realizing it, leaving no time for emergency maneuvers. For long trips, it's best to stop at a service area every two hours to drink some water and check tire pressure. Safety is far more important than saving time.

[AliceRose]

Let me explain this from a mechanical perspective. Running a car continuously at high speed for 12 hours is an endurance test for the powertrain. After an ultra-long drive with my SUV, I clearly felt increased engine vibration at idle—caused by excessive piston ring wear. The cooling system faces even greater pressure, with increased risk of coolant boiling, and the radiator fan was spinning like crazy. When transmission fluid temperature exceeds 120°C, it oxidizes and fails; I had to change the oil earlier than scheduled afterward. Brake disc heat fade is even more dangerous, potentially increasing emergency braking distance by over 20 meters. Remember to let your car catch its breath—stop for at least half an hour every 300 kilometers, and popping the hood for cooling is the safest bet.

[LaGage]

Neither humans nor cars can withstand such abuse. Last week, I drove cross-province on the highway and after 8 hours, my eyelids were heavy with fatigue—I had to pull over at a rest area and sleep for half an hour to recover. Driving for over 12 hours disrupts melatonin levels, causing reaction delays of more than half a second. The constant steering wheel vibration can also trigger white finger disease—my fingers went numb for hours. I recommend keeping peppermints in the car to stay alert, and podcasts are better than music at fighting drowsiness. Ideally, have two drivers to take turns, especially avoiding night driving. If you must go solo, break the trip into segments—don’t gamble with your life.