What is the black plastic panel under the bumper called?

[MacEli]

The plastic panel under the front bumper is called a deflector. The deflector is fixed under the bumper with screws or clips and can be removed by the user. The main function of the deflector on the car is to reduce the resistance during high-speed driving and lower the vehicle's fuel consumption. Material of the deflector: Originally, the deflector was a safety feature of the car, made of thick steel plates or metal. However, as cars evolved, aesthetics and lightweight became increasingly important, leading to its gradual replacement with plastic. Plastic is easy to shape but also prone to deformation, so it is important to protect the deflector. Function of the deflector: To reduce the lift generated when a car is driving at high speed, car designers not only improved the car's exterior but also installed a downward-sloping connecting panel under the front bumper. The connecting panel is integrated with the front skirt of the car body, with suitable air inlets in the middle to increase airflow and reduce the air pressure under the car.

[WalterMarie]

Speaking of that black plastic piece under the bumper, mechanics usually call it the lower guard plate or lower trim panel—it's essentially a mudguard and anti-scratch component. Once when I was reversing and hit the curb, this panel cracked with a loud snap. Only when replacing it did I learn it's divided into front lip and rear lip sections. The front lip replacement for my SUV cost over 800 yuan, claimed to be OEM with air deflector channels. Remember not to use high-pressure water jets on the seams during car washes—sand trapped in gaps can break the clips. Don't underestimate this part—it protects fog light wiring harnesses from ice chunks when driving rough roads in winter.

[VonCharles]

I work on construction sites all year round, so scratches on the plastic underbody panels are common. The official name for this panel is the bumper lower spoiler, and some vehicle manuals refer to it as the 'front/rear bumper lower grille.' Its main purpose is to prevent stones from damaging the paint and to optimize underbody airflow. Last time this panel on my car got deformed, the repair shop guy said that new-energy vehicles prefer PP material, while traditional fuel-powered cars mostly use ABS plastic. If you're installing an aftermarket one, make sure to leave enough ground clearance—too low, and it's doomed to fail over speed bumps.

[SanGeorge]

Every off-roader knows the importance of this black plastic piece, called a skid plate in the community. When I modified my Jimny, I replaced it with a metal competition bumper, but for daily driving, the plastic one is more practical. The OEM part is thoughtfully designed with deflector fins to reduce wind noise. Maintenance is a breeze—just apply some plastic restorer to prevent aging and cracking. If you hear strange noises after crossing water, it's likely the mounting clips have come loose, and any roadside shop can fix it for 50 yuan.

[KayleeMarie]

Last time, the technician at the 4S shop told me that the plastic piece at the bottom of the front bumper is called a deflector, mainly serving to protect the radiator and reduce wind resistance. It's recommended to spray a layer of undercoating for new cars, especially in areas where de-icing agents are used in the north. Pay attention to check for cracks on the panel, as frozen and brittle plastic can easily break during emergency braking at minus twenty degrees Celsius in winter. Aftermarket parts on certain online platforms cost around a hundred yuan, but the clip positions often don't align properly. I learned this the hard way and ended up replacing it with an original factory part.

[OHope]

Remember when my hatchback had its first maintenance, the service order stated 'replace front lip spoiler,' which actually refers to this plastic piece under the bumper. Female car owners, don’t be intimidated by technical terms—it’s just a protective panel. When washing the car, remind the attendant to clean the grooves where the panel meets the body, as accumulated mud can cause the clips to rust and seize. If you hear a buzzing noise, it might not be the panel’s issue but rather a detached inner liner. This panel must meet national standards, with a required thickness of over 2.3mm to qualify as a compliant part.