Let go of the steering wheel on a straight, level road and your car should track forward without drifting. If it pulls noticeably to the left or right, something is wrong. The question is what — because the five most common causes range from a quick fix to a safety issue that needs attention today.
The Five Most Common Causes
Wheel Alignment Out of Specification
Wheel alignment is the most frequent cause of a car pulling to one side. The alignment angles — particularly caster — control how the wheels track relative to the vehicle centreline. When the caster angle differs between the left and right front wheels, the car pulls toward the side with the lower caster value. This happens gradually after pothole impacts, kerb strikes, or simply through normal wear on suspension components over time.
The pull from alignment is typically gentle and consistent — the car drifts steadily in one direction rather than lurching. It's present at all speeds and doesn't change when you brake. If this describes what you're experiencing, a wheel alignment check is the first thing to book.
The Pothole Connection
A single significant pothole impact can knock one wheel's alignment out while the others remain within specification. The car may not pull dramatically — but one tyre will be wearing faster than the others from that point on. If you've hit a pothole recently and the car now pulls slightly, book an alignment check before the tyre wear becomes visible.
Uneven Tyre Pressure
This is the easiest cause to check and the easiest to fix. A tyre that's significantly underinflated on one side creates more rolling resistance on that side, pulling the car in that direction. Check all four tyre pressures with a gauge — don't rely on the visual appearance of the tyre, as a tyre can be 10 PSI underinflated without looking noticeably flat.
If correcting the pressures eliminates the pull entirely, the problem is solved. If the pull returns within a few days, you have a slow puncture — the tyre is losing air through a small nail or valve leak. A puncture repair will fix this permanently.
Brake Caliper Sticking
A sticking brake caliper applies partial braking force to one wheel even when you're not pressing the brake pedal. This creates a strong, consistent pull toward the affected side. The distinguishing feature is heat — a sticking caliper makes the affected wheel significantly hotter than the others after a short drive. You may also notice a burning smell, and the car may feel sluggish to accelerate.
This is a safety issue. A sticking caliper reduces braking efficiency and can cause brake fade. It needs to be inspected and repaired promptly — don't delay this one.
Worn or Mismatched Tyres
Tyres with significantly different tread depths on the same axle create unequal grip, which can cause a pull. This is most noticeable in wet conditions. The tyre with less tread has less grip, and the car pulls toward it. Running a new tyre on one side and a worn tyre on the other is the most common scenario.
Fitting tyres of different brands or constructions on the same axle can also cause pulling, even when both tyres are new. Always fit matching tyres in pairs on the same axle.
Suspension Component Wear
Worn control arm bushes, a collapsed spring, or a worn ball joint can all cause a car to pull. These faults are less common than alignment or tyre issues, but they're worth considering if the pull is accompanied by clunking noises over bumps, a change in ride height, or if the alignment keeps going out of specification shortly after being corrected.
Suspension wear is often the underlying cause of repeated alignment problems — if you find yourself needing alignment corrections every few months, the suspension components should be inspected.
How to Tell Which Cause You Have
| Symptom | Most Likely Cause | Urgency |
|---|---|---|
| Gentle, consistent drift at all speeds | Wheel alignment | Book this week |
| Pull disappears after inflating tyres | Tyre pressure / slow puncture | Check pressures now |
| Strong pull + hot wheel + burning smell | Sticking brake caliper | Book today |
| Pull worse in wet, better in dry | Mismatched / worn tyres | Book soon |
| Pull + clunking over bumps | Suspension wear | Book soon |
| Pull after hitting a pothole | Alignment knocked out | Book this week |
The Road Camber Test
Before concluding that your car has a fault, check whether the road itself is causing the apparent pull. Most roads are cambered — slightly higher in the centre and sloping toward the edges to allow rainwater to drain. On a cambered road, a perfectly aligned car will drift slightly toward the lower side (usually the left on UK roads).
The test: find a quiet, flat car park or a road with a centre line that you know is level. If the pull disappears on a flat surface, road camber is the cause — not your car. If the pull persists on a flat surface, the fault is in the car.
What Happens If You Ignore a Pull
The consequences depend on the cause. An alignment pull causes progressive tyre wear — one tyre wears faster than the others, and you'll need to replace it earlier than expected. A sticking caliper causes brake fade and, in severe cases, a brake fire. Mismatched tyres reduce wet-weather grip across the whole axle.
None of these improve on their own. The pull you notice today will be worse in three months, and the tyre wear or mechanical damage will be more expensive to address.
What to Book First
Start with tyre pressures — check them yourself with a gauge. If pressures are correct and the pull persists, book a wheel alignment check. The alignment check will also reveal whether there are any suspension issues causing the misalignment. If the pull is strong and accompanied by heat or a burning smell from one wheel, book a brake inspection first.
Book a Wheel Alignment Check at IQ Tyres
We use the Hunter HawkEye Elite — camera-based alignment to 1/100th of a degree. Free initial measurement. Mitcham, South London.