What does a trailing arm do?

A trailing arm is part of a vehicle’s trailing-arm suspension system. The trailing arm is the piece of the suspension system that connects the vehicle’s axle to its chassis. It’s job is to act as a pivot point and stop the rear axle or rear spindle from moving forward or rearward during operation of the vehicle.

In addition to the trailing arm itself are the trailing arm bushings. These are rubber or polyurethane components that act as cushions and reduce friction between the suspension parts.

BMW

BMW AG is a German automobile and motorcycle manufacturer that was established over 100 years ago in March 1916. They also own Mini and Rolls Royce, after taking over the two British marques in 2000 and 1998 respectively.

How popular is BMW in the United Kingdom?

BMW makes luxury vehicles and is possibly most famous for its sports saloon models. In 2018, BMW had 1.9m vehicles on the roads in the UK, a number that has been steadily increasing each year for the past decade.

As one of the ‘big 3’ German marques, along with Audi and Mercedes, BMW carries a strong reputation for making high-quality stylish vehicles, and have captured a large section of the UK market.

Luxury family and business models for every driver

Probably most popular for the 3 Series and 5 Series saloon models, BMW has got every possible angle covered for the more discerning drivers.

The full range includes everything from the 1 Series city car to the full-size saloons and sports coupes of the 7 and 8 Series models.

To provide everything you’d ever need for family motoring there’s a seven-seat MPV, their range of X model SUVs, and since 2014, the introduction of their plug-in electric i models. Top it all off with their M model high-performance supercars, the Z4 convertible and the i8 Roadster—and you’ve got the full package.

BMW: High performance on and off the track

BMW has a successful history in a range of motorsports.

They have been significant performers in touring car racing and rally driving, enjoyed success in Formula One with the BMW Sauber team, and BMW cars have been regular competitors and winners at Le Mans since the race’s early years.

BMW’s reliability and reputation

BMW ranked 16th place out of 30 car brands in the What Car? Reliability Survey in 2018. BMW hasn’t always had the best reputation for reliability but to rank alongside marques such as Honda, Volkswagen and Fiat they’re holding their own alongside plenty of the other big names.

How often should a trailing arm need replacing?

A trailing arm should be replaced if it gets damaged or if the bushings become worn. Because the trailing arm bushings are made from rubber they will deteriorate over time and will eventually have to be replaced.

Because the arm and bushings form a crucial part of your vehicle’s suspension system, they should be replaced as soon as you notice any of the symptoms mentioned above.

The law, vehicle regulations and your MOT

The trailing arm and the bushes are important parts of the suspension. Wear to these bushes usually takes place slowly, often you only find out that you have worn bushes after an MOT test. Deteriorated bushes are in fact one of the most frequent MOT advisories.

Symptoms of worn suspension bushes include a bumpy ride and unstable feel to the car. It’s important to get an issue like this fixed fast to ensure the safety of your car for you and your passengers.

What happens when we do a trailing arm replacement on your car?

Our certified mechanics will:

• Inspect your suspension system, including the trailing arm.

• If the trailing arm is cracked or damaged they will fit a replacement.

• They will advise if any related parts need to be replaced.

• They will check that all parts have been fitted correctly and test drive the car.

What causes a trailing arm to break?

A trailing arm will begin to fail if the bushes become worn out. The brushes act as cushions and reduce friction between the suspension parts, therefore if they’re cracked or worn the suspension system will not operate properly. Driving over large bumps or on uneven road surfaces often may also damage your suspension system over time.

When should a trailing arm be replaced?

A trailing arm should be replaced if it gets damaged or if the bushings become worn. Because the trailing arm bushings are made from rubber they will deteriorate over time and will eventually have to be replaced.

What are the signs of a bad trailing arm?

Usually, there a few signs you can look for:

• Clunking noises from the back of your car

• Vehicle won’t stay in a straight line or sways to one side when driving

• Your rear tyres are wearing unevenly and excessively

• Loose steering when turning corners

What happens during a trailing arm replacement?

Our certified mechanics will:

• Inspect your suspension system, including the trailing arm.

• If the trailing arm is cracked or damaged they will fit a replacement.

• They will advise if any related parts need to be replaced.

• They will check that all parts have been fitted correctly and test drive the car.

Can you drive with a broken trailing arm?

You should not drive with a bad trailing arm. Failing to repair a broken or cracked trailing arm could lead to separation of that side of the axle. Continuing to drive is dangerous for you, your passengers and other road users as it’s only a matter of time before further, more serious damage occurs.

What happens if you don't change a bad trailing arm?

Failing to repair a broken or cracked trailing arm could lead to separation of that side of the axle. It could also result in other parts of your vehicle’s suspension system becoming more damaged meaning more costly repairs down the line.