In short. When a car pulls, the moment it pulls is the best clue. A pull at a steady speed points first to the tyres (pressure, wear, or a tyre built slightly cone-shaped) and the alignment, after you have ruled out the slope of the road; a pull that appears only when you brake points to the brakes; a pull only under hard acceleration is torque steer. Check the pressures first, then swap the front wheels left to right: if the pull changes sides, a tyre is the cause, and if it stays, the car is. If the pull came on suddenly, after a hit or after brake work, or the car swerves when you brake, have it checked before you carry on.
Pull, drift, off-centre wheel: three different complaints
Workshop documents separate three things that drivers often describe with one word. Subaru's 2019 bulletin defines a steering pull as a tendency to pull or drift left or right at speed, not under acceleration, with the steering wheel held straight; an off-centre steering wheel as one that must be held at a slight angle to keep the car going straight; and torque steer as a pull during full acceleration that needs more steering correction than usual (Subaru 04-25-19R). GM's 2014 bulletin for the Corvette makes the same split: if the car runs straight but the wheel sits off-angle, that is a steering wheel angle concern, corrected by setting the front toe, not a pull (GM PIC5975).
An older word, lead, means the same as a pull: GM's 1975 manual defines it as the straying of the vehicle from a straight path on a level road with no pressure on the steering wheel (Buick 1975).
When does it pull? The causes sorted by moment
We built this table by reading the maker documents side by side. A cause can appear in more than one row; the row shows where it shows most.
| When it pulls | Most likely causes | What the sources say | Sources |
|---|---|---|---|
| Steady speed, steering wheel straight | Road camber; uneven pressures; uneven wear; tyre construction (conicity, ply steer); alignment; worn suspension parts | Subaru lists crowned road, conicity or ply steer, mismatched or unevenly worn tyres, alignment and worn or badly repaired suspension | Subaru; GM 1975; Michelin Canada |
| Only when braking | A sticking or seized caliper; brakes that brake unequally left and right; unequal pressures | GM 1975 lists uneven braking among the effects of unequal pressure on one axle; Michelin Canada names a seized caliper and uneven pad wear | Michelin Canada; GM 1975; MOT 1.2.1 |
| Only under hard acceleration | Torque steer | Subaru: a pull during full acceleration that needs more correction than usual | Subaru |
| After new tyres or a tyre swap | A tyre with conicity; mismatched tyres on one axle | The swap test isolates it; the MOT fails different sizes or structures on one axle | Saab/GM; GM 2014; MOT 5.2.3 |
| After an alignment | Cross-caster or cross-camber; an off-centre wheel mistaken for a pull; a tyre pull the alignment cannot fix | GM's procedure swaps the wheels before the alignment rack | GM 2014; GM 1975 |
| Suddenly, or after a hit | A flat or damaged tyre; a bent part | Michelin Canada: pull over and inspect for a flat or damaged tyre | Michelin Canada |
At a steady speed: start with the road and the pressures
The road itself. Roads slope sideways so that water drains off, and a car on such a slope drifts down it. GM's Corvette bulletin tells the technician to test in both left- and right-sloping lanes, and says that a car following the road crown is normal operation and performing to design intent; in that case the rest of the procedure is not to be done (GM PIC5975). The 1975 manual asks for the road test on a level, uncrowned road, in both directions.
How strong is the effect? The sideways share of a car's weight on a slope is its weight times the sine of the slope angle. For a car of 1,500 kg, with slopes we took as examples:
| Cross slope (assumption) | Sideways force on the car | Share of the car's weight |
|---|---|---|
| 1 % | 147 N | 1 % |
| 2 % | 294 N | 2 % |
| 3 % | 441 N | 3 % |
Our arithmetic (m × g × sin(arctan s), g = 9.81 m/s²). We did not read a road design standard for the camber of a normal lane, so these slopes are examples, not measured values. One reference point: the US brake standard FMVSS 135 runs its tests on a surface with no more than 2 % gradient perpendicular to the direction of testing (49 CFR 571.135, S6.2.2); our reading is that a regulator accepts that much sideways slope even on a test surface.
The test: drive the same straight stretch in both directions, or in both lanes. If the pull always goes towards the kerb, it is probably the road; if it goes the same way whatever the slope, look at the car. Michelin Canada gives the same test: a car that pulls left in the right lane and right in the left lane is following the camber. Where traffic drives on the right (United States, Canada), the kerb-side slope pushes a car to the right; in Great Britain and Australia, where traffic drives on the left, it pushes it to the left.
The pressures. The 1975 GM manual lists steering lead among the effects of unequal pressure on the same axle, and Subaru's procedure starts by setting the pressures to the specification before anything else. Michelin Canada says a tyre significantly lower on one side creates uneven rolling resistance. Use the figures on the door pillar or in the handbook, cold; our tyre pressure guide explains where to find them.
Uneven wear. Michelin Canada says tyres with different tread depths have different rolling radii and pull towards the more worn side. The difference is not small. A 225/45 R18 tyre is about 659.7 mm across (18 × 25.4 + 2 × 0.45 × 225). If one front tyre has 5 mm less tread than the other, its radius is 1.5 % smaller; if the two turned the same number of times, the larger would cover about 15 m more per kilometre. The differential lets the wheels turn at different speeds, so this shows the size of the mismatch, not a measured drift; run your own size in the tyre size calculator, and see our guide to tyre wear patterns for what the wear itself says about the car.
Tyre conicity: the pull no alignment removes
A tyre can be built so that it rolls like a very slightly conical one. GM's 1975 manual explains the mechanism: off-centre belts on radial tyres can make the tyre develop a side force while rolling straight, and if one side of the tyre is a little larger in diameter than the other, the tyre tends to roll to one side. Subaru calls it "remaining cornering force of tire (tire conicity or ply steer)". Michelin Canada calls conicity a rare manufacturing defect and says most tyre makers and retailers will replace a tyre confirmed to have it under warranty. You cannot see it.
The swap test, as three maker procedures write it
| Procedure | First step | If the pull reverses | If the pull stays the same way | Rear tyres |
|---|---|---|---|---|
| GM, 1975 | Inflate to recommended pressure, test on a level uncrowned road both ways, swap front tyres side to side (if the lead disappears, it is corrected; replace the tyres if roughness results) | Fit a known good tyre on one front side, then on the other, to find the faulty one; if the lead remains, adjust cross-caster | Put the tyres back in their original position and check the alignment | "Rear tires will not cause lead" |
| GM, Corvette 2014 | Rate the pull 1 to 10 in left- and right-sloping lanes, then swap front wheel and tyre assemblies left to right | Follow the radial tyre lead/pull procedure to isolate the tyre | Go to the alignment rack | Not covered |
| Saab and GM, 2011 | Road test on a smooth level surface, cross-switch the front tyres | Cross-switch left front with left rear, then right front with right rear | Measure the wheel alignment | A rear tyre can be the one replaced |
Sources: Buick 1975, figure 31-13; GM PIC5975; Saab WIS.
The documents disagree on the rear. The 1975 text says rear tyres do not cause lead; the 2011 procedure moves front tyres to the rear and can end in replacing a rear tyre. We cannot settle it; what you can take from both is that the front swap comes first and is the most telling.
Two cautions before you swap. A directional tyre (arrow on the sidewall) cannot change sides without being remounted on the rim, and a staggered set with different sizes front and rear cannot change axles: our tyre rotation guide explains both. And if you change a wheel yourself, use the car maker's torque and order, as set out in the wheel nut torque guide. Never put any part of yourself under a car held only by a jack: it must be raised and resting on axle stands.
When it pulls only under braking
A pull that appears when you press the pedal and goes away when you release it is a brake matter until proven otherwise. Michelin Canada describes a seized caliper as applying constant braking force on one side, names most often a sticking caliper on the side the car pulls towards, or uneven pad wear, and advises having brakes and tyres inspected together when a brake pull appears. A brake that keeps working when you are off the pedal also turns its work into heat, so a wheel that is much hotter than its partner after a drive points the same way; do not touch the disc or caliper to find out.
The MOT test puts numbers on it. The brake tester measures each wheel, and the manual fails a car as major when "the braking effort from any wheel is less than 70%" of the maximum recorded from the other wheel on the same axle, or, on a road test, when "the vehicle deviates excessively from a straight line"; it is dangerous below 50 % on a steered axle (MOT manual, 1.2.1 (b)). Significant brake effort with no brake applied, "indicating a binding brake", is major (1.2.1 (f)).
What do those thresholds mean in force? Our arithmetic, with stated assumptions: a 1,500 kg car braking at 0.5 g, 70 % of the braking on the front axle (the same total in every row), front track 1.56 m.
| Front wheels | Left wheel | Right wheel | Difference | Turning moment on the car |
|---|---|---|---|---|
| Balanced | 2,575 N | 2,575 N | 0 N | 0 |
| Weak wheel at 70 % (MOT major limit) | 3,030 N | 2,121 N | 909 N | about 709 N·m |
| Weak wheel at 50 % (MOT dangerous limit, steered axle) | 3,434 N | 1,717 N | 1,717 N | about 1,339 N·m |
The force difference at the MOT's major limit is three times the sideways force of our 2 % slope example, and it appears exactly when the car is slowing hard. These are sums under assumptions, not a measurement of any car. The point is the order of size: in our reading, a brake imbalance the tester would fail is large enough to be felt in the steering.
If the car swerves under braking, have it checked before you drive it again. A pull in a straight line at a steady speed is a nuisance to diagnose; a swerve when you brake is a braking fault. Our guide on wheel balancing covers the separate case of a vibration through the pedal or wheel.
When it pulls only under acceleration
This is torque steer, and Subaru's definition ties it to full acceleration and high engine torque. The same bulletin says the diagnosis must first rule out a steering pull and an off-centre wheel, which drivers mistake for torque steer, and it applies only with the original wheels, tyres and suspension in place (the bulletin was written for the 2018-19 STI).
After an alignment, new tyres, a hit or brake work
After an alignment. If the wheel is off-centre but the car runs straight, the toe or steering wheel was set off; go back to the workshop with the printout. If the car pulls, GM's 2014 procedure is the order to ask for: pull rated in both lane directions, front wheels swapped left to right, and only then the rack. When a tyre is not the cause, GM's correction is to adjust caster across the axle: for a pull to the right, more caster on the right and/or less on the left, splitting the change about the nominal values, and cross-camber only if that is not enough. The 1975 manual says the same in its own way: make the lead side 1° more positive in caster than the other. These are a technician's adjustments for one model, not settings to copy.
After new tyres. A new pull after new tyres points first to a tyre with conicity: swap the fronts left to right. Mismatched tyres can also contribute (Subaru lists them), and in Great Britain the MOT fails tyres of different sizes, or of different structure, on the same axle as major (MOT manual, 5.2.3 (b) and (c)). Which axle gets the new pair is a separate question: see new tyres, front or back.
After a pothole or a kerb. Michelin Canada says that if the pull appeared suddenly after an impact or is getting worse, pull over and inspect for a flat or damaged tyre. A pull that comes with a new noise or a vibration may also be a bent wheel or a damaged part: see alloy wheel repair for what can be fixed. In Great Britain a wheel bearing with excessive play is a major MOT defect, and dangerous where directional control is impaired (5.1.3).
After brake work. A pull that starts after new pads, discs or a caliper is the brake case above. Take it back to whoever did the work.
After new wheels. The wheel itself rarely creates a steady pull, but a wheel and tyre package changes the tyres, which can bring conicity, and a different width or offset changes the forces on the steering. Onyx Forged does not recommend a size or an offset: the car maker's documents set the range, and our guide to what size wheels fit my car explains what each figure changes. An alignment check after fitting, done to the car maker's figures, settles the question.
What the rules say, country by country
| Country | Text | What it says about a pull |
|---|---|---|
| Great Britain | MOT inspection manual, sections 1 and 5 | Major: one wheel's brake effort under 70 % of the other on an axle, or excessive deviation on a road test; binding brake; different tyre sizes or structures on one axle. Dangerous: under 50 % on a steered axle |
| United States (new vehicles) | FMVSS 135, last amended 8 June 2022 | Brake tests in a 3.5 m (11.5 ft) lane; steering corrections are permitted, and stops are made "without any part of the vehicle leaving the lane", with no rotation of more than ±15° (S6.2.3, S6.5.4.1, S6.5.4.2) |
| United States (state inspection, example) | 67 Pa. Code § 175.80 (Pennsylvania) | Rejection if the car swerves "so that any part leaves the 12-foot lane" when stopping, or for a braking or steering malfunction including "shimmy, wander, pull" ((f)(3), (f)(4)) |
| Canada (new vehicles) | Motor Vehicle Safety Regulations, section 135 (current to 21 September 2026) | Light vehicles of 3,500 kg GVWR or less must meet Technical Standards Document No. 135 |
| Australia (Queensland, example) | Queensland Light Vehicle Inspection Manual, effective 7 July 2026 | Road test reason for rejection: "Service brake does not operate correctly, without vibration or pulling to one side when applied" |
Sources: MOT section 1 and section 5; 49 CFR 571.135; 67 Pa. Code § 175.80; Canada MVSR; Queensland manual.
FMVSS 135 and the Canadian standard apply to new vehicles; periodic inspection in the United States, Canada and Australia is set by each state, province or territory. We read Pennsylvania and Queensland as examples, not the others.
Frequently asked questions
Why does my car pull to the right?
Often the road where traffic drives on the right: roads slope towards the kerb, a car drifts that way, and GM treats a car that follows the road crown as normal (in Great Britain and Australia the same slope pushes to the left). If it pulls right in every lane and in both directions, check the pressures, then swap the front wheels left to right to see whether a tyre is the cause.
Why does my car pull to one side when braking?
Most often a brake that grips harder on one side or does not release, such as a seized caliper. The MOT fails a car when one wheel's braking effort is under 70 % of the other's on the same axle. Have it checked before you drive it again if it swerves.
Why does my car pull after an alignment?
Either the steering wheel is off-centre (the car runs straight, the wheel is crooked: a toe setting), or the pull comes from a tyre that no alignment corrects, which is why GM swaps the front wheels before adjusting anything.
Can a new tyre make a car pull?
Yes. A tyre with conicity develops a side force while rolling straight. Swap the front tyres left to right: if the pull changes direction, a tyre is the cause. Michelin Canada says a confirmed conicity defect is usually replaced under warranty.
Is it safe to drive a car that pulls to one side?
A slight drift with the road camber is normal. A sudden pull, one after a hit or brake work, or a swerve when braking is not: check for a flat or damaged tyre and have the car checked before you carry on.
Is a pull to one side an MOT failure?
In Great Britain, a car that "deviates excessively from a straight line" on a brake road test fails as major, and so do several causes of a pull: one wheel braking under 70 % of the other on an axle, a binding brake, different tyre sizes or structures on one axle, a wheel bearing with excessive play. In Queensland, a brake pulling to one side is a reason for rejection.
Can the rear tyres make a car pull?
The documents disagree. GM's 1975 manual says rear tyres will not cause lead; the 2011 Saab and GM procedure swaps front tyres to the rear and can end with a rear tyre replaced. Start with the front swap.
What is torque steer?
In Subaru's definition, a pull during full acceleration that needs more steering correction than usual; not at a steady speed or under braking.
Wheels from Onyx Forged
A pull is a matter for the tyres, the brakes and the geometry, and the fix comes from the car maker's figures. If you are choosing new wheels, the Onyx Forged catalogue shows wheels made to order for a given car, designed to JWL/VIA standards.
Sources
- Subaru of America, Service Bulletin 04-25-19R, Torque Steer Diagnostics and Repair Procedure (25 April 2019, revised 28 August 2019).
- General Motors, PIC5975, Steering Pulls To The Right At Highway Speeds (March 2014).
- 1975 Buick Service Manual, section 3, wheels and tires; Saab 9-4X (2011), Radial Tire Lead/Pull Correction.
- Michelin Canada, Symptom: pulling to one side; Michelin US, Car pulls to the right or left (updated 21 April 2026).
- GOV.UK, MOT inspection manual, section 1: brakes and section 5: axles, wheels, tyres and suspension.
- 49 CFR 571.135, FMVSS No. 135, Light vehicle brake systems, via the Legal Information Institute.
- Canada, Motor Vehicle Safety Regulations, section 135.
- Pennsylvania Code, 67 Pa. Code § 175.80; Queensland Light Vehicle Inspection Manual (effective 7 July 2026).
All pages were read on 16 October 2026.
The Onyx Forged design office.