Can the wheel size of a vehicle be modified?
4 Answers
If the modification of the wheel hubs is not approved by the traffic management department in advance, it is illegal and the vehicle will not pass the annual inspection. The size of the car's wheel hubs cannot be modified. Doing so is illegal, and if caught on the road, you may face fines and vehicle seizure. Vehicles cannot be altered arbitrarily, and it is advised not to change the wheel hub size. Modifying the wheel hub size can lead to decreased power, reduced vibration absorption, increased fuel consumption, and is also illegal. Therefore, it is best not to make such changes. If you wish to change the body color, model, performance, purpose, or structure of the vehicle, or replace the frame, body, or engine, the owner must apply to the vehicle management office for a modification registration.
You can certainly change the wheel size, but this shouldn't be done too casually. My neighbor switched to 19-inch large wheels last year, and ended up with two tire punctures within two weeks. Modifying wheels requires considering the vehicle's structural tolerance—for instance, the suitable sizes differ between SUVs and sedans. You also need to accurately calculate the new wheel's J-value; otherwise, the tires might protrude beyond the body and easily scrape the fenders. I recommend consulting a professional modification shop to measure the original parameters, ensuring the wheel diameter change doesn't exceed 2 cm for safety. The braking system could also be affected, requiring readjustment of the caliper position. Additionally, the tire aspect ratio needs to be modified accordingly; otherwise, the speedometer will be inaccurate. Although regulations allow minor modifications, oversized wheels will definitely fail the annual inspection.
I've seen many people change their wheels just for looks, only to end up with a lot of trouble. The most immediate effect after increasing the size is that the tires become harder, making speed bumps painfully jarring. Last year, when helping a friend upgrade to 20-inch wheels, I noticed the fuel consumption increased by 1.5 liters directly, due to the increased friction surface adding resistance. Wheel size isn't the bigger the better; it needs to match the car's height for a harmonious look. Also, pay attention to the wheel material—cast wheels are cheaper but prone to deformation, while forged ones cost three times as much but are more durable. After modification, wheel balancing and four-wheel alignment are must-dos; otherwise, the steering wheel will shake at speeds above 120 km/h. It's advisable to keep the original wheels, just in case they're needed for inspection.
Wheel size can be modified, but don't change it blindly. I once bought new wheels only to find the bolt pattern didn't match and they couldn't be installed. A common misconception is that bigger is always better, but in reality, performance needs to be balanced. For example, lightweight wheels can indeed improve handling on the track, but for daily driving, thin tires are more susceptible to rim damage from potholes. When modifying, pay attention to the ET value—if the value is too small, the wheel track becomes wider, affecting cornering stability. Also, check if the wheel's center bore matches; otherwise, you'll need to add hub centric rings later, which may cause vibrations. In terms of price, domestic forged wheels are available at around a thousand yuan, while imported brands cost double but offer more stable quality.
