What Subframe Bushings Do for Your Suspension

Your vehicle’s suspension system contains several bushings that absorb road bumps, reduce road noise, and minimize friction between linked components. Subframe bushings do just that and help improve your vehicle’s handling and comfort. However, just like any other part, subframe bushings can deteriorate over time and compromise your safety.

What Are Subframe Bushings?

Let’s first define subframes and bushings before discussing subframe bushings. The subframe of a vehicle is a structure that supports the engine, steering, and suspension components. Subframes typically have a pair of bushings on the front and rear sides of the frame, but more complicated designs can have up to eight bushings.

Bushings vary according to design, material, and application. They’re typically made from rubber or polyurethane. They’re placed between moving components, acting as an interface and a cushion for these components as well as anti-vibration or flexible mountings.

Subframe bushings are rubber or polyurethane cushions designed to isolate vibrations and road noise while enhancing a vehicle’s handling. They’re specially made for specific vehicles and models. Some subframe bushings are only available as part of a new or reconditioned subframe and cannot be purchased individually from the OEM manufacturer.

What Are the Different Types of Subframe Bushings?

Different materials affect how your subframe bushing performs. Here are two of the common types of subframe bushings.

Rubber Bushings

This type of bushing can dampen vibrations and noise well due to the flexibility of its material. However, its flexibility makes it susceptible to having air gaps, resulting in deflection. Rubber bushings are also more likely to warp and tear.

Polyurethane Bushings

Polyurethane bushings are more durable than rubber bushings because they’re made of rigid plastic. They’re stiff and don’t deflect due to air gaps, making them ideal for performance driving or situations that require less movement between the car’s structural parts. However, these bushings transmit more vibration and noise due to their stiffness. Poorly lubricated polyurethane bushings can also squeak.

What Do Subframe Bushings Do?

Subframe bushings prevent surfaces in the attachment points from directly touching and rubbing against each other while the connected parts move. These bushings also serve as padding for the joints that allow linked components to move while dampening friction, vibration, noise, and harshness.

What Are the Symptoms of a Damaged Subframe Bushing?

The joints and connected parts in the suspension system are subjected to more stress as the subframe bushing wears out. Here are the common symptoms of a damaged subframe bushing.

Loud Noises

Road noise can be transmitted to the cabin without bushings to dampen it. You may hear clunking, creaking, or rattling noises from the subframe when turning or driving over uneven roads.

Alignment Issues

The subframe can be misaligned as a result of deformed bushings, which affect the position of steering and suspension components.

Steering Problems

Worn-out subframe bushings can throw off a vehicle’s wheel alignment, potentially leading to steering abnormalities.

Uneven Tire Wear

Changes in wheel alignment due to bad bushings can cause the tires to wear out unevenly.

What Causes Subframe Bushings to Wear Out?

Frequent movement and heavy loads can cause subframe bushings to wear out.

Exposure to extreme temperatures, salt, oil, and other elements can also cause these bushings to harden, crack or warp.

What Can I Do to Keep My Subframe Bushing in Good Condition?

Subframe bushings are generally resistant to vibrations and road shock, but they can still fail over time regardless of your driving habits. There’s no proven method for extending the life of your subframe bushings. Once the bushing dries out, you have no other choice but to replace it.

When to Replace Your Subframe Bushing?

There’s no recommended timeframe for checking your vehicle’s bushings. Different driving conditions and stresses determine whether your bushings fail. If your vehicle exhibits symptoms of subframe bushing failure, make sure to get your vehicle checked. As a precautionary measure, you can ask a mechanic to inspect your subframe bushings whenever you have your vehicle’s suspension serviced.

Cracked bushings can cause irreparable damage to your subframe, which could present another set of problems. It’s important to replace your bad subframe bushings as soon as possible to prevent issues with your suspension and steering.

How Much Does a Subframe Bushing Cost?

Aftermarket subframe bushing replacements can cost anywhere between $30 and $300 depending on factors such as brand and vehicle application. If you have a professional install the bushings, you can also expect to pay labor costs. Some subframe bushings can usually be bought individually or as part of a set or kit. However, in severe cases of bushing failure, you might need to replace your entire subframe.