Why is my steering pulling to one side or heavy?

If the car drifts to one side on a flat road, start with the tyres. Uneven pressures, uneven wear or a damaged tyre are the most common reasons. After that, wheel alignment, a sticking brake caliper and worn suspension parts are the next suspects.

Heavy steering is a separate symptom with different causes. It can come from low tyre pressures, a power steering fluid or pump problem, a slipping auxiliary belt, or a fault in the electrically assisted system on some vehicles. A warning light is a strong hint.

What makes a car pull to one side?

A car pulls when something differs between the left and right wheels. The usual causes are in the list below, roughly in the order a garage would check them.

• Different tyre pressures, or a tyre that is leaking slowly.
• Uneven tyre wear or a tyre with an internal fault.
• Wheel alignment out of adjustment after a kerb or pothole strike.
• A brake caliper that is sticking or a pad that is dragging.
• A worn or damaged suspension or steering part.

What can I check myself first?

Check the pressures of all four tyres when cold, using the figures in the handbook or on the door pillar sticker, and look for bulges, cuts or uneven wear. Remember that the legal minimum tread depth is 1.6 mm.

Then see if the pull changes. Does it pull when braking only, or all the time? Does it pull in both directions or only one? Note whether the steering wheel sits straight when you drive in a straight line, as an off-centre wheel can suggest an alignment issue. Road camber can also cause a gentle drift, so test on a flat, quiet road. If one wheel is hot after a short drive, a brake may be dragging.

Why is my steering suddenly heavy?

Hydraulic power steering needs fluid, and a low level, a leak or a failing pump can make the wheel hard to turn, often with a whine. A loose or worn drive belt can do the same. Many newer cars use an assisted system that warns you on the dashboard when it has a fault.

Heavy steering can also come from very low front tyre pressures, seized joints or a worn steering rack. It may be heavier only at parking speeds, or only when the engine is cold, and either detail is useful to pass on. Because the causes differ so much, avoid guessing and check the fluid level only if your handbook shows how.

What does a garage do about steering faults?

A garage will inspect the tyres, check the steering and suspension for play, check the brakes for drag, and measure wheel alignment on suitable equipment. If the steering is heavy, it will look at the fluid, belt, pump and rack or at the warning system.

Cost drivers include the cause found, how many parts are involved and whether alignment is adjusted afterwards. We would only give a firm quote after the car has been inspected.

When should I stop driving?

Stop driving if steering suddenly becomes much heavier, the wheel has more play than normal, the car wanders and needs constant correction, or a steering or power steering warning light comes on together with a change in feel. Steering is a critical safety system. Having the car checked before a long trip is far better than discovering a fault on the road.

If the car only drifts slightly and feels otherwise normal, drive carefully to have it checked soon, avoiding fast roads in the meantime.