Why you need underwings: protection, noise insulation and durability of the car

Many car owners perceive the slats (lockers) as a secondary element that can be ignored until it falls off or starts to rattle. However, these plastic or composite shields perform a critical function in the overall vehicle protection system. They are installed in the wheel arches and serve as the first barrier between the aggressive external environment and the metal of the body, as well as suspension elements. Without quality lockers, the car becomes vulnerable to a variety of factors that can shorten its lifespan.

The main task of these elements is to prevent the ingress of stones, sand, gravel and chemical reagents that fly from under the wheels when moving. It's not just a matter of aesthetics, but protection from corrosion and mechanical damage. In the conditions of Russian roads, where the quality of the coverage often leaves much to be desired, and in winter the roads are generously sprinkled with salt, the presence of whole under-wings becomes a matter of preserving the integrity of the car. Ignoring their condition can lead to costly repairs to the rapids and arches.

In this article, we will discuss in detail what functions the underwings perform, how they differ in materials and why installing or replacing them is a priority for every responsible car owner. We will look at the technical aspects of their work and give practical advice on maintenance. Understanding how this element works will help you save significant money on body repairs in the future.

Basic function of body and LCP protection

The primary purpose of locker installation is the physical protection of paint coating (LCP) and metal from abrasive effects. When a car moves on highways or city roads, the wheels lift huge masses of small particles. Sand, small pebbles and gravel fly at high speed, creating the effect of sandblasting. If there were no barrier, this flow would directly hit the inner walls of the arches and rapids. In time. wear-and-wear The stains are then cast into the metal, which is the way to the stain.

In addition to mechanical effects, the pads protect against chemical aggression. In winter, the roads use mixtures of salt and reagents, which, when hit by metal, cause an instant chemical oxidation reaction. The plastic from which the locker is made is inert to salts and acids. He takes a hit on himself, not allowing aggressive slime to contact the body for a long time. This is especially true for modern cars, where arches are often made of thin metal, prone to rapid rotting.

⚠️ WARNING: Even if you notice a small crack or chip on the underwing, don’t delay repairs. Through the damaged area, dirt and water will enter the space between the locker and the body, creating a "greenhouse effect" and accelerating the corrosion of hidden cavities.

It is important to understand that the underplate protects not only the visible part of the arch, but also the hidden cavities. Water and dirt, getting behind a plastic shield, can stagnate there for years if ventilation or drainage is disturbed. Therefore, the correct installation with the observance of gaps for air circulation is as important as the presence of the element itself. Tightness It is not necessary, you need proper circulation of air flows to dry.

Protection of suspension and engine elements

The slats play an important role in protecting not only the body, but also the components located in the engine compartment and under the bottom. At the front of the car, the arches often form part of the fairing, directing air currents to cool the engine and brake system. Disturbance of geometry or lack of locker can lead to water getting on the ground generatorStarter or spark plugs, which is especially dangerous in rainy weather or when washing the engine under pressure.

Also under protection are the steering elements and brake lines. Rocks flying out from under the wheels of oncoming cars or raised by their own wheels at speed can damage the rubber anthers of steering tips or brake hoses. This poses a direct threat to traffic safety. The locker takes the hit on itself, cushioning the impact of solid objects. In some car designs, for example, Land Rover or ToyotaThe underwings further protect plastic ducts and sensors.

In winter, the absence of a backflight can lead to freezing of mechanisms. Snow porridge, stuffed into the wheel arch, can freeze around the suspension levers or hand brake cables (if they pass in this area). This is fraught with jamming of the suspension elements or the inability to open the pads. The plastic shield smooths out temperature changes and prevents direct contact of snow with mechanical parts, allowing them to function in a more stable mode.

Noise insulation and aerodynamics of the car

Few people think, but the underplates are an important element of acoustic comfort in the cabin. Noise from tyre rolling, gravel strikes and suspension work is transmitted to the body through the wheel arches. The plastic sheet, especially if it has a woolly coating or additional noise insulation on the back side, extinguishes these vibrations. Without it, the cabin is filled with a hum, which at track speeds becomes very tiring for the driver and passengers.

From an aerodynamic point of view, the wings help to form the right air currents around the wheels. The wheel creates turbulence when rotating, and the smooth surface of the locker allows air to flow around the arch more smoothly. This reduces the overall aerodynamic drag of the car, which has a positive effect on fuel consumption and control stability at high speeds. For sports models and crossovers, this is especially true. criticallyBecause it affects downforce.

Modern manufacturers often use aerodynamic wings with special protrusions and channels. They direct air to cool the brake discs, which prevents them from overheating during heavy operation. The absence of such an element or its replacement with an artisanal analogue without taking into account aerodynamics can lead to overheating of the brake system and a decrease in the effectiveness of braking.

Manufacture materials: plastic, metal or fibre

In the modern market of auto parts you can find underwings made of various materials. Each of them has its own advantages and disadvantages that must be considered when choosing a replacement. The most common material is polypropylene. It is characterized by high elasticity, which allows it to restore its shape after light shocks, and resistance to temperature changes. However, in a cold, cheap plastic can become fragile.

Metal backs (often found as standard on older models) VAZ or GAZA) are reliable but corrosive. Over time, they rot, become covered with rust and can fall off in pieces. Their main plus is stiffness, but the minus is the lack of elasticity and noise insulation properties. Fibre (fiberglass) lockers are a compromise option. They are stronger than plastic, do not rust, but when hit hard can crack, and they are more difficult to restore.

When choosing a material, you should pay attention to the presence of a fuzzy coating (felt lining) from the inside. This coating is better at absorbing noise and prevents snow and ice from sticking. Smooth plastic, on the other hand, helps snow slip, but can be noisier. For harsh winter conditions, the optimal choice is considered to be underwings made of frost-resistant polyethylene with additional noise insulation.

Materials	Strength	Noise insulation	Resistance to corrosion	Price.
Polypropylene (plastic)	Medium	Good.	Tall.	Low.
Metal	Tall.	Low.	Low (rusting)	Medium
Fiberglass (fibre)	Tall.	Medium	Tall.	Tall.
Polyurethane	Very high.	Great.	Tall.	Tall.

Typical malfunctions and causes of wear

Even the best quality slats eventually become unusable. The most common problem is mechanical breakdown The stains (shoulders, sleeves) and the sleeves themselves. When driving on bad roads, a large stone or ice lump can get into the gap between the wheel and the arch, which will simply pluck a piece of plastic. Also, the cause of breakdown is often the owner himself, who, with careless washing under high pressure or when servicing the underhood space, steps on the locker or pulls it.

Another common cause of failure is material fatigue and ultraviolet exposure. Over time, the plastic loses its elasticity, fades and begins to crumble. This is especially true in cars that spend a lot of time in the sun. Cracks appearing in the mounting places, over time, grow, and the under-wing begins to dangle, creating an annoying noise and risking getting under the wheel.

⚠️ Note: If the under-wing starts rubbing against the tire (this is easily heard by the characteristic rustle when turning the steering wheel), the operation of the car must be stopped immediately. Friction of plastic against rubber can lead to a tear of the tire on the move.

Often problems arise after unqualified repair or tuning. For example, the installation of wheels of larger diameter (non-standard dimension) without trimming the arches leads to constant contact of the tire with the underwing on the bumps. This is guaranteed to result in rapid wear of both elements. Before installing new rubber or discs, always check the gaps in the arches.

Rules for installation and maintenance of lockers

Installation of the wings is a procedure that can be performed independently in garage conditions, but it requires care and adherence to technology. The main rule is to use the right fastener. Do not use ordinary black screws that instantly rust. It is best to use galvanized screws with a press puck or a special plastic fastener (pistons), coming in the kit. Metal clips over time oxidize and “stick” to the body, which will make future dismantling difficult.

Before installing a new element, it is necessary to conduct an audit of the hidden cavities of the arch. This is the perfect time to process metal. corrosion-proof. While the slats are removed, you have access to hard-to-reach places that are usually closed. The application of anticor will prolong the life of the body for many years. Also, check the condition of the wiring that often runs along the arches (for example, wires to the turn signals or ABS sensors).

When installing it is important not to pull the mounts. Plastics must be able to move micro-movements (temperature expansion). If you pinch it dead, at the first frost or impact it will burst around the fastening points. You also need to make sure that all drainage holes in the lower part of the arch (if they are provided by the design) are not closed by the locker, otherwise water will accumulate inside.

Nuances of winter installation

When installing the underwings in winter in the cold, the plastic becomes very rigid. It is recommended to make new lockers in a warm room for several hours before installation or gently warm them with a building hairdryer. This will reduce the risk of breaking the antennae of the anchorages when snapping.

The impact of the underwings on the cost of car maintenance

Timely replacement of damaged underwing is an investment in preserving the value of the car. A potential buyer when inspecting the car is first of all striking body defects. Rotten arches, bubbling paint on the doorsteps and a lack of plastic protection signal that the car was not being followed. Restoring the geometry of the arches and painting them are much more expensive than buying a set of new lockers. In addition, the presence of whole underwings indicates careful operation.

Lack of protection can lead to failure of more expensive nodes. For example, dirt on the bearing of the hub due to a torn anther or locker reduces its resource at times. Replacing a hub bearing is a more time-consuming and expensive procedure than replacing plastic. Thus, petty-saving In the form of slats can lead to a multiple increase in the cost of STO in the medium term.

Owners of cars with plastic slats should also consider that this element often suffers first in parking incidents or hitting high curbs. When selling cars, the presence of original, not "slanted" underwings (without holes from screws and wire) is a small but pleasant bonus, confirming the accuracy of the owner.

FAQ: Frequently Asked Questions

Can I drive without the slats if they are removed?

Short-term driving without wings is acceptable, but on a permanent basis it is harmful to the car. You risk damaging the LCP with stones, speeding up the corrosion of arches and rapids, and contaminating the under-hood space. In addition, in the rain, the water will actively spray the engine and electrics.

What is better to wash the wings in winter?

It is best to use self-service washers with active foam and pressure rinse function. It is important to direct the jet not only to the visible part, but also to the space behind the slat (if there is access) to wash away the accumulated salt and reagents. Regular washing prevents accelerated rotting of metal under the plastic.

Why did the slat start to creak or knock?

Most likely, the mounts weakened or the plastic pistons broke. Also, the cause may be the deformation of the locker itself, because of which it began to touch the tire or suspension elements. It is necessary to lift the car, remove the wheel and check the reliability of fixing all mounting points.

Should I lubricate the slats?

Lubricate them is not necessary, but you can treat the inside with special anti-adhesive compositions (like “anti-ice” for the body), so that there is less linden snow and dirt to the plastic. This will make it easier to wash and reduce the weight of the adhesive mass.

Can I paint the slats in body color?

Technically possible, but not practical. Plastic under the wings is elastic and deforms when impacted, because of which the paint will quickly crack and peel off. Black is also better at hiding dirt. If you want aesthetics, it is better to buy quality lockers with a carbon fiber texture or matte coating.