Can you replace just two tires on a 4WD or AWD vehicle?

Yes, but only in specific situations. If your vehicle has part-time 4WD that you mostly drive in 2WD, replacing two tires as a matched pair is usually acceptable. If it’s a full-time AWD or automatic 4WD system, you generally should replace all four—unless the new pair can be matched very closely in rolling circumference to the existing pair (typically within about 2/32–3/32 inch of tread depth difference, or roughly 0.5% in diameter). Always check your owner’s manual and your tire shop’s guidance for your exact model before proceeding.

Contents

What actually determines whether two tires are enough?
Why matching tire size and wear matters
General rules you can use
When replacing only two tires is reasonable
When you should replace all four tires
How to do it right if you replace only two
Costs, shaving, and practical tips
Bottom line
Summary

What actually determines whether two tires are enough?

The answer hinges on your drivetrain type and how precisely your tires match in size and wear. Full-time AWD and many automatic 4WD systems rely on center differentials or clutch packs that assume all four tires rotate at nearly the same speed. Mismatched tire diameters force those components to work constantly, which can cause heat, binding, or premature wear. Part-time 4WD systems, by contrast, are typically driven in 2WD most of the time, making two-tire replacement less risky—provided you only engage 4WD when tires closely match.

Why matching tire size and wear matters

Rolling circumference is what the drivetrain “sees.” Even small diameter differences make one axle try to turn faster than the other, pushing the center differential or transfer case to slip or bind. That can damage viscous couplers, multi-plate clutches, or gears. The practical proxy is tread depth: the more worn a tire is, the smaller its rolling circumference becomes. Keeping the difference small protects the driveline.

General rules you can use

The following points summarize widely accepted practices from automakers and tire specialists for 4WD/AWD vehicles. Use them as a guide alongside your owner’s manual.

Full-time AWD or automatic 4WD: Replace all four tires unless the new pair can be shaved or otherwise matched to within about 2/32–3/32 inch (1.6–2.4 mm) tread depth of the remaining tires, and all four are the same size, brand, and model.

Part-time 4WD (primarily driven in 2H): Replacing two tires as a matched pair is typically acceptable; avoid using 4WD until all four tires closely match in diameter.

Keep rolling circumference differences under roughly 0.5% when AWD/4WD is in use; as a quick rule of thumb, 2/32–3/32 inch tread depth difference is the common limit. Some OEMs are stricter; consult the manual.

Always install the newer tires on the rear axle, even on FWD and AWD, to reduce oversteer risk in wet or slippery conditions.

If only one tire is damaged and others are significantly worn, consider shaving a new tire to match or replacing all four.

These practices minimize driveline stress and preserve predictable handling, while balancing safety and cost.

When replacing only two tires is reasonable

Here are typical scenarios where a two-tire replacement can be done without compromising the vehicle—assuming correct matching and placement.

Your vehicle is part-time 4WD and you operate it in 2WD almost exclusively; you will avoid 4WD use until tires match closely.

Your AWD/4WD vehicle’s remaining two tires are relatively new with shallow wear, and a new pair can be shaved or closely matched to within 2/32–3/32 inch of tread depth difference.

You can source the exact same tire model, size, and load/speed rating as the existing pair.

In these cases, you can keep costs down while maintaining driveline health and traction balance.

When you should replace all four tires

In the situations below, replacing all four tires is typically the safest, most cost-effective choice in the long run.

Full-time AWD or automatic 4WD with remaining tires significantly worn versus new (more than 3/32–4/32 inch difference).

Mixed brands or models across axles, or size discrepancies beyond OEM guidance.

Manufacturer guidance explicitly requires four-tire replacement (common with some AWD systems).

Uneven tire wear from alignment or suspension issues that makes matching impractical.

Doing all four prevents driveline stress, avoids warranty disputes, and restores balanced handling and braking.

How to do it right if you replace only two

If you decide a two-tire replacement is appropriate, follow this process to protect your vehicle and ensure safety.

Measure tread depth on the two remaining tires at several points across the tread to confirm even wear.

Buy the same size, model, and load/speed rating; confirm manufacturing specs match (including revolutions per mile if available).

Ask your tire shop about shaving new tires to match the remaining pair within 2/32–3/32 inch if needed.

Mount the new tires on the rear axle to improve stability in wet/icy conditions.

Perform an alignment check and correct any suspension issues that caused uneven wear.

Reset and verify TPMS, then rotate per the vehicle’s schedule to keep wear even.

Avoid using 4WD (on part-time systems) until the diameter mismatch is within the recommended tolerance.

These steps help ensure your tires work together and your driveline remains protected.

Costs, shaving, and practical tips

Tire shaving: what it is and when it helps

Some shops can “shave” a new tire, removing tread so its rolling circumference matches your partially worn tires. This is useful on AWD vehicles to avoid buying four tires when only two are needed. It’s most feasible when your remaining tires have moderate wear and are a current model still available new.

Placement matters: why new goes on the rear

Putting the deeper-tread tires on the rear reduces the risk of sudden oversteer in rain or snow. Even on front-drive vehicles, industry testing shows stability is better when the rear has more traction. The same applies to AWD/4WD.

Watch for warning signs

If you feel driveline binding in tight turns, hear whining from the center differential/transfer case, or smell hot fluid after a drive, stop using 4WD/AWD and have the system inspected. These can be signs of tire mismatch or driveline damage.

Bottom line

You can replace just two tires on many 4WD/AWD vehicles, but only if the remaining pair closely matches in size and wear, and you install the new pair on the rear. Full-time AWD often demands all four match very closely—when in doubt, replace all four or have new tires shaved to match. Check your owner’s manual and lean on a reputable tire shop to measure and advise.

Summary

Replacing only two tires on a 4WD/AWD vehicle is sometimes acceptable: it’s more workable on part-time 4WD in 2WD mode and on AWD if the new pair can be matched within about 2/32–3/32 inch of the remaining tread depth. Always install the new pair on the rear, keep brands/models identical, and consider tire shaving to match diameters. If differences are larger or your system is full-time AWD with strict tolerances, replace all four to protect the driveline and maintain safe handling.

Do you really need to replace all four tires on AWD Reddit?

If it’s a fwd, rwd, or 4×4 vehicle you can just throw a used tire on that’s similar in tread to the other side or just replace them in pairs with matching tires. However if it’s an awd vehicle you will need to swap all 4 if not you can damage stuff and it can lead to costly repairs.

Do you need to change all four tyres on a 4×4?

Yes, for all-wheel drive (AWD) and four-wheel drive (4×4) vehicles, it is strongly recommended to replace all four tires at the same time to prevent damage to the drivetrain. A new tire has a larger diameter than a worn one, and this difference can cause the AWD system’s computer, transmission, and transfer case to work overtime to compensate for the varied rotational speeds, potentially leading to costly damage over time.

Why replacing all four is necessary for AWD/4×4 vehicles:

Maintains uniform tire diameter: Replacing all four tires ensures that all tires have the same tread depth and, therefore, the same overall diameter.
Protects the drivetrain: In an AWD or 4×4 system, mismatched tire diameters cause one axle to spin faster than the other, forcing the differentials and transfer case to work constantly to equalize the speeds. This excessive, continuous strain can cause them to overheat and fail prematurely.
Consistent performance: Uniform tread depth provides consistent grip and handling, which is crucial for maintaining control, especially during emergency maneuvers or in challenging conditions.

What happens if you don’t replace all four:

Driveline damage: The constant need to compensate for size differences puts undue stress on the drivetrain components, leading to wear and tear.
Unpredictable handling: Uneven tire wear can lead to inconsistent performance and unpredictable vehicle behavior.
Confused traction control: The AWD computer may incorrectly interpret the difference in wheel speeds as a loss of traction, leading to false readings and system confusion.

An exception:

If you only have one damaged tire but the other tires are very new and have a tread depth within the manufacturer’s recommended tolerance (often 3/32 of an inch difference), you may be able to get the new tire shaved to match the tread depth of the existing tires. However, for most situations where the existing tires are significantly worn, replacing all four is the safest and most effective solution.

Do you have to get four new tires for 4 wheel drive?

The conventional wisdom among drivers of all-wheel-drive vehicles has been that when they need to replace a single tire, every tire should be replaced. Doing that ensures that the AWD system won’t experience unbalanced wear and that there’s balanced traction at all four corners.