Why Is Your Car Pulling To One Side?

Driving a car that pulls to the left or right can be distracting, frustrating and tiring as you try to keep it travelling in a straight line.

There are a number of reasons for a vehicle to pull to one side, including everything from an underinflated tyre to failed suspension parts. Before any work is done, it's important to identify when the pulling happens:

• Is it consistently pulling to one side during every journey? 
• Is it only when you brake?
• Is it only when you accelerate? 
• Did it start after new tyres were fitted? 
• Does the steering wheel shake as well?

By figuring out when the vehicle starts to pull to the left or right, possible causes can be investigated and potential solutions can be put in place.

1. Car pulls to one side
2. Car pulls to one side after alignment
3. Car pulls to one side when braking
4. Car pulls to one side when accelerating
5. Car pulls to one side after new tyres fitted
6. Car pulls to one side and the steering wheel shakes

CAR PULLS TO ONE SIDE

Common reasons for a car to constantly pull to one side while driving are uneven tyre pressure and improper wheel alignment.

UNEVEN TYRE PRESSURE

Fixing a car pulling to the left or right could be as simple as putting more air into a tyre or letting some air out. Under- or over-inflated tyres can affect the way your car leans and subsequently have an impact on the vehicle's alignment. In addition, an underinflated tyre has more rolling resistance, making the pull more noticeable.

If you don't know what the correct tyre pressure is for your car, or you're unsure how to check the tyre pressure, we've put together a comprehensive tyre pressure guide.

As soon as you notice your car pulling to one side, the first thing you should do is check the tyre pressure. If the car is still veering to the left or right, something else is causing the issue.

IMPROPER WHEEL ALIGNMENT

The most common reason for a car pulling to one side is incorrect wheel alignment. If this is the case, when you release the steering wheel, the car will drift in one direction and the steering wheel is unlikely to return to its normal position. In addition, if you inspect your car tyres, you're likely to notice uneven tread wear.

Your car's wheel alignment can be altered by driving over a pothole or hitting the kerb; however, sometimes it slowly skews to one side over time. The wheel alignment process involves a technician adjusting the wheels, tyres and suspension back to the manufacturer's settings using specialist alignment technology and tools.

You can choose to have either a 2 or 4 wheel alignment. As the names suggest, a 2 wheel alignment only focuses on two wheels, whereas a 4 wheel alignment will correct both front and rear axles and ensure the vehicle's stability.

Here at Dowleys, we offer both 2 and 4 wheel alignment, but would always recommend having all four wheels correctly aligned to prevent any potential issues from incorrect rear axle alignment.

CAR PULLS TO ONE SIDE AFTER ALIGNMENT

Unfortunately, getting the car's wheels re-aligned with the correct tyre pressure won't always solve the issue of it pulling to the left or right. If you still experience pulling, the technician might not have taken the road 'crown' into account.

Essentially, the crown is a slope that allows for drainage. When roads are built, engineers never build them flat - this enables rain to run off and reduces the risk of flooding. While unlikely, it's possible that the wheel alignment technician hasn't considered this.

Far more likely is that there is a worn suspension or steering part. If that is the case, no matter how much the wheel alignment is reset, the vehicle will continue to pull to one side. In this instance, it's always best to get a qualified mechanic to have a look.

CAR PULLS TO ONE SIDE WHEN BRAKING

If the pull only happens when the brakes are applied - unlike a wheel alignment problem where the pull will be consistent - there will be an issue with the braking system. This could be the result of a stuck brake caliper or worn suspension parts.

STUCK BRAKE CALIPER

Calipers are powered by the hydraulic brake system and apply pressure to the brake pads to bring the car to a stop. Each wheel has its own caliper and if one of them is sticking, the vehicle will pull to that side.

Alternatively, there could be a problem with the wheel cylinder or a hydraulic fault. The unnecessary friction on the brake as a result of any of these faults will cause it to get very hot and you might notice a burning smell as well as the car pulling to one side.

The braking system is a critical safety component; as such, it needs to be professionally inspected and fixed by a trained mechanic.

WORN SUSPENSION PARTS

If the brake system is working as expected, the pull when applying the brakes could be caused by worn suspension parts shifting position. For example, lower control arm bushings that need replacing may allow the arm to move when braking, subsequently changing the position of the wheel and causing the vehicle to pull to one side.

A common symptom of worn suspension parts is a quick pull on the steering wheel when the brakes are applied which subsides as they're released. Throughout a car's lifetime, most of the suspension system will need replacing. As the parts become worn, they often cause the car to pull to the left or right as they shift or lean to one side.

CAR PULLS TO ONE SIDE WHEN ACCELERATING

Similar to a pull when braking, a vehicle drifting to one side when accelerating is not caused by improper wheel alignment. It's almost exclusively the result of something called torque steer.

TORQUE STEER

Although it mostly impacts front-wheel drive (FWD) cars, torque steer can cause a car to pull to one side as it initially accererates. 

DIY TEST: Put the car in neutral and coast it down a quiet road without having your hands on the wheel. If it doesn't pull to one side, wheel alignment is not the problem, and it could be torque steer.

There are numerous causes for torque steer, including a tie rod with too much slick, a ball joint that has too much movement or a deteriorating lower control-arm bushing. More complicated causes include an unequal drive shaft angle caused by an engine or suspension that isn’t level.

If you notice your car pulling to one side after acceleration, it's best to let a professional technician check for any underlying issues.

CAR PULLS TO ONE SIDE AFTER NEW TYRES FITTED

If you've never noticed your car pulling to the left or right before, but it suddenly starts after new tyres have been fitted, it's likely that the new tyre(s) have a different tread pattern or have been poorly manufactured.

DIFFERENT TREAD PATTERNS

Every tyre is manufactured with a certain tread pattern. Different brands and even different tyres from the same brand will have different tread patterns which don't have the same wear and rolling characteristics.

Something as simple as replacing one tyre in a set with one that doesn't match could cause a pull, especially if that tyre is on the front. It's advisable to always try to change tyres in pairs and place the new ones on the rear axle.

TYRE CONICITY

When the steel belts (under the tread of the tyre) aren't perfectly aligned, the tread rubber can harden in a slight cone shape causing tyre conicity. As you might expect, a tyre that isn't completely cylindrical will cause a pull.

Fortunately, it’s an easy problem to see with the naked eye and is very apparent straight away in new tyres. Most warranties will also provide cover for tyre conicity, so you can get a replacement free of charge.

CAR PULLS TO ONE SIDE AND THE STEERING WHEEL SHAKES

A shaky steering wheel and a car that pulls to the left or right is doubly annoying and indicates that the problem is either to do with wheel balancing or just a bad tyre.

WHEEL BALANCING

Wheel balancing is not the same as wheel alignment. To ensure that weight is distributed evenly around the entire wheel, small balancing weights and counter weights are added to the rim.

An unbalanced wheel will cause the tyre to vibrate which then causes the steering wheel to shake. If there's too much weight on one side of the wheel, it can cause the car to pull to that side as well as shaking the steering wheel.

TYRE SEPARATION

Similar to tyre conicity, sometimes tyres are just manufacturered poorly which can mean they don't roll smoothly or in a straight line. Tyre separation occurs when air has forced the steel belts to separate from the tyre frame.

Typically, you can spot tyre separation at low speeds because the wheel and steering wheel will start to shake or shimmy. Tyre separation is potentially very dangerous because it can cause the tyre to completely fail unexpectedly.

If you feel any of the tyres or the steering wheel start to shake, get a professional mechanic to take a look as soon as possible.

FIXING YOUR CAR'S STEERING PULL AT DOWLEYS GARAGE

Here at Dowleys Garage, we have qualified technicians that can diagnose the reason your vehicle is pulling to one side. Using the latest equipment, we can implement a repair whether you need a wheel alignment and balancing or replacement suspension parts..

We're proud members of the Trust My Garage Scheme so you can be sure that any work we carry out is in the best interests of your safety. Head over to our Carterton Tyres Centre for more information about the services we provide.