The Car-Owners Guide to Buying Suspension Control Arms & Parts

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The Car-Owner's Guide to Buying Suspension Control Arms and Parts on eBay

Today's cars are expected to pound up and down the motorway year after year, coping with substantial stresses while still providing a smooth ride. To smooth out any ride, a vehicle needs a robust suspension system. A car's suspension must allow for accurate steering control, and a smooth ride, as well being sufficiently hardy to carry heavy weights at speed.

The car's suspension is a critical automotive system. To ensure continued performance, the motorist should be able to identify the signs and symptoms that the suspension system is in need of repair and where to source quality suspension control arms and parts.

Increasingly, motorists are turning to eBay to find all manner of automotive parts for a variety of make and model of cars. On eBay there are thousands of current listings for suspension control arms and related parts for many of today's popular motor cars. These suspension parts include original manufacturer's parts and third party replacements, or OEMs. In order for the user to find the parts they need on eBay, they need to know how to perform a keyword search and how to sort search results using eBay's various search filters. This breadth of  range combined with eBay's competitive pricing makes eBay the ideal online venue for buying suspension control arms and parts.

How to Find Control Arms and Related Parts on eBay

It is easy to find the control arms and related parts for your car on eBay. The car-owner simply types a search phrase into the search bar on the eBay home page. A good phrase to use would be 'control arms and parts'. This is a fairly generic term. One could use a more specific search phrase, but it is recommended that the car-owner start with a generic search phrase and then use various search filters to sort the tens of thousands of current listings for control arms and related parts. To conduct an effective search on eBay, a car-owner should first do his homework on what parts constitute a car's suspensions systems, and the types of suspension control arms available.

What Are Suspension Control Arms?

The suspension plays a crucial role in the safe handling of a vehicle and the control arms are crucial components in a vehicle's suspension system. Therefore, any problems that arise in a suspension system's control arms can adversely affect how a motorist is able to handle his car on the road.

The Purpose of Control Arms

The control arms sit between the chassis and axles of the car on the one end, and the body of the car on the other. A control arm is a mechanism that reduces the intensity of the shocks transmitted from the wheels to the main body of the car. To an extent, the control arms help reduce this shock by dissipating it, although that is not their only function. The control arms also feed information back to the driver via the steering mechanism, thereby allowing the driver to remain aware of the state of contact between the wheels and the road.

This tactile feedback is essential for a driver to maintain effective control over the vehicle. A driver knows that something is wrong with one of the suspension control arms when the car starts to handle differently on the road. The driver may notice a loss of precision. This is due to damage to the suspension bushings, or bushes, that are attached to the control arms. These bushings can in time become worn out, and when this happens, the car's handling begins to deteriorate. The suspension system also becomes very noisy.

Types of Suspension Control Arms

There are two principal types of control arm suspension: double wishbone and the Macpherson strut suspension.

Double Wishbone Suspension

This suspension architecture involves two broadly 'A'-shaped control arms used in conjunction with each other. They sit parallel to each other, with one sitting higher up and the other lower down. The two open ends of the 'A' are attached to the body of the car, and the pointed ends are attached to the wheel. There are variations of this structure that can involve uneven shaped sides to the 'A', but the principle remains the same. The shock absorber and spring coil link the two wishbones, acting to absorb the shock of the road before it reaches the chassis of the vehicle.

Located between the wishbone arms and the chassis are bushings, which act as vibration dampers. Typically these bushings, or bushes, are made of resilient synthetic rubber. The bushings act to cushion the impact and forward or backward movements between the wishbones and chassis. As noted above, when bushings wear out, the suspension system becomes noisy and the handling of the vehicle is impaired.

The precise angles between the wishbones and the wheel and other elements of the suspension setup, such as the camber angle, can greatly influence the handling of the car. That said, double wishbone suspension allows a fair degree of movement compared with other suspension architectures, which helps account for its comfortable ride and hence its popularity over other systems. In fact, double wishbone suspension is also known as 'independent' suspension, in recognition of the independent movement available to each of the two control arms.

Macpherson Strut Suspension

Macpherson strut suspension is another type of suspension architecture that employs control arms. Unlike double wishbone suspension setups, the Macpherson strut uses just one control arm, with the upper control arm replaced by a vertical telescopic strut attached to a coil spring. The strut mechanism and the coil spring act together to form a shock absorber.

Advantages and Disadvantages of the Two Types of Suspension

Double wishbone suspension setups and Macpherson struts each have their strengths and weaknesses. This table sets out the principal advantages and limitations of each.

 

Vertical Movement

Noise Level

Cost and Complexity

Double Wishbone

Permitted

Quieter

High

Macpherson Strut

Restricted

Noisier

Lower

Many modern cars use one or the other of these types of suspension, with small, compact cars often using Macpherson struts, and larger, more expensive cars using the double wishbone suspension. However it is not always that clear cut. Some Porsches, BMWs and Mercedes Benz cars also use Macpherson strut suspension, possibly to achieve a more sporty 'feel'.

Sorting Results Based on Make and Model of Car

The car manual should have details of the type of suspension on a particular car. However, eBay takes a lot of guesswork out of choosing the right suspension control arms. All automotive parts listed on eBay are categorised according to the make and model of car. This includes listings for suspension control arms and parts.

For example, if the car-owner has an Audi A4, he selects the appropriate search filter on the results page, and the local search engine returns only those listing for suspension control arms that are compatible with the Audi A4. If the car-owner finds that his car is not listed as an option, he should contact a dealership or the manufacturer.

Sorting Results Based on Condition and Manufacturer

The buyer is also able to sort results based on the manufacturer. For example, popular manufacturers for Audi suspension parts include Febi and Quinton Hazell.

eBay also allows for the sorting of results based on the condition of the part. While there are certainly used parts available for sale, it is advisable that a car-owner buy the best, new automotive parts that he can afford. The purchase of used suspension control arms can prove to be quite complicated. The buyer needs to read item descriptions very carefully and look for signs of critical damage in the photographs that accompany the listings. Buying used suspension control arms is best left up to a car-owner with an especially critical eye.

Assessing the Seller

Those eBay sellers with the highest feedback scores for customer service and quality of merchandise are referred to as Top-rated Sellers. These sellers can be counted on to be especially knowledgeable about what they sell. If the car owner has any questions for the seller, the buyer can contract the seller through the contact link in the seller's profile. The profile page also includes feedback left for the seller by previous buyers. 

Conclusion

Control arms are key elements in double wishbone suspension setups, and are also an important part of Macpherson strut suspension systems. The control arms sit between the wheel and the chassis of the car, and dampen the shocks transmitted to the body of the car. Therefore, control arms help insulate the car against shocks from the road, and also feed steering information back to the driver, allowing for better and safer handling on the road. The control arms require replacement when the driver begins to lose precise control over the handling of the vehicle on the road.

eBay has thousands of listings for control arms and related parts. These include original equipment parts from major car manufacturers, as well as third party replacement parts. eBay's search engine allows the user to search for compatible parts based on the make and model of car. While there are listing for used parts, it is advisable that when shopping for replacement parts for a car's suspension that the car-owner, unless he is experienced in assessing the quality of used automotive parts, stick to listings for new suspension control arms and parts.

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