Is it better to change all 4 tyres at once?
In most cases, replacing all four tyres at the same time is the safest option, especially for vehicles with all-wheel drive (AWD) or four-wheel drive (4WD). For typical front- or rear-wheel-drive cars, replacing two tyres can be acceptable if those tyres are identical in size, brand, tread pattern and wear—and positioned correctly on the axle with proper rotation. The decision depends on your drivetrain, tyre age, and budget, but the emphasis remains safety, balance, and predictable handling.
When four tyres at once makes the most sense
The following points explain why replacing all four tyres is recommended in some cases, and how it improves safety and performance.
Key scenarios for a full set
Before listing the practical considerations, this section outlines why a full set is often the best choice for certain drivetrains and conditions.
- AWD/4WD systems rely on similar rolling circumferences across all wheels; replacing all four tyres ensures nearly identical circumference, reducing drivetrain strain and the risk of uneven torque distribution.
- Matching tread depth across all four tyres improves braking performance, cornering stability, traction control, and hydroplaning resistance, particularly in wet or icy conditions.
- New tyres on all corners promote uniform wear, more predictable handling, and easier maintenance over the life of the set.
- Using a single set of tyres across all four corners can avoid warranty proration and the potential for inconsistent grip between old and new tyres.
- For safety-sensitive seasons (for example, winter driving), having four matched tyres across the vehicle provides the best overall stability and traction.
In practice, replacing all four tyres minimizes drivetrain stress and helps maintain balanced braking and steering across the tyre life cycle.
Factors to consider for your vehicle
Before making a decision, assess your vehicle’s drivetrain, tyre age, and operating conditions.
What influences the replacement choice
These considerations help determine whether a full set or a pair is appropriate for your car.
- Drivetrain type: AWD/4WD vehicles are more sensitive to circumference differences and tyre wear, making a full set replacement more advisable to avoid mechanical or electronic stability issues.
- Circumference tolerance: manufacturers commonly advise keeping rolling circumference differences between tyres within about 2-3% across all four tyres.
- Size and model matching: ideally, tyres on all four corners should be the same brand, model, size, and tread pattern.
- Tire age vs tread depth: tyres age with time and can fail or lose performance even if tread depth remains above the minimum.
- Seasonal considerations: for regions with harsh winters, replacing all four with winter tyres is common for safety and performance.
- Warranty and policy: mismatched tyres can affect warranty or eligibility for replacement under some manufacturers' policies.
- Budget and availability: replacing four tyres can be more costly upfront but may save on uneven wear and handling problems later.
Bottom line: symmetry, correct axle placement, and matching specifications matter for safety and performance.
Practical steps for replacing tyres
Here's a practical checklist to consider when you're ready to replace tyres, whether you replace two or four.
Two tyres or four tyres: what to choose
These steps help you decide the number of tyres to replace and how to proceed to maintain safety and handling.
- Inspect tyres for uneven wear, cuts, bulges, or ageing; check the date stamp to gauge age.
- Ensure replacement tyres match the current tyres in size, load index and speed rating, and ideally on all four corners.
- Decide on the number of tyres to replace based on drivetrain: four for AWD/4WD if possible; two may be acceptable on two-wheel-drive vehicles if you cannot replace all four.
- Choose tyres with matching tread pattern and performance characteristics to maintain balanced handling.
- Have tyres mounted and balanced by a reputable shop; ensure proper wheel torque and follow the vehicle's manual for recommended pressures.
- Consider a wheel alignment if you notice pulling, uneven wear, or after large changes to suspension components.
- Schedule regular tyre rotations to achieve even wear over the life of the set.
- Keep records of tyre manufacture dates and warranty information for future reference.
Following these steps helps ensure safety, performance, and optimal wear across the tyre set.
Summary
Across most modern vehicles, changing all four tyres at once is the safest and most reliable option for AWD/4WD vehicles, protecting the drivetrain and improving stability. For non-AWD cars, replacing two tyres can be acceptable if the tyres are identical in size, brand and tread and are installed on the correct axle, but replacing all four is often the best long-term investment in safety and performance. Always aim to keep tyres matched across all four corners, account for tyre age, and plan rotations to maximise safety and value.
