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AWD Tire Replacement Myth: Is It Always True?

AWD Tire Replacement Myth: Is It Always True?

If you drive a 4x4, you've probably heard the AWD tire replacement myth: that you can't just replace one or two tires at a time—you've got to replace all four. If you've come here looking for reassurance that this isn't true, we're sorry to tell you it's more fact than myth.

But are there any exceptions to the rule? Is it really that dangerous to swap out tires one by one on your 4x4? Here's what to know.

Key Takeaways:

  • The AWD replacement myth is that you have to replace all four tires at once on an all-wheel drive or 4x4 vehicle.
  • It's almost always best to replace all four tires on your AWD vehicle because of the way the computer distributes torque to each tire.
  • There may be some exceptions if you need to repair or replace one tire or one pair of tires from a newer set, such as patching a damaged tire or shaving new tires to match the old treads.

The AWD Tire Replacement Myth

If the myth holds true, then any time you need to replace one tire on a 4x4 vehicle, you need to replace all four tires. The general idea behind it is that if one or two tires are worn out more than the other two or three, the difference can cause added strain to your drivetrain.

What Happens When You Mismatch Tires

When you mismatch tires on a 4x4, you force your drivetrain to distribute inconsistent and even unnecessary amounts of power to certain tires. This is why replacing tires on AWD vehicles is a little different than replacing tires on two-wheel drive vehicles.

Graphic showing that a new tire will go further in one rotation than an older tire will

To explain, consider what happens to tires as you drive. Little by little, the tread goes down. If this happened at the same rate for all four tires, then in theory, every tire would have the same level of tread at all times. When one tire (or a pair) loses tread faster than the others, it becomes a little bit smaller. It may seem like an insignificant change, but since smaller tires revolve more times than larger tires over the same distance, even millimeters of difference are significant over potentially millions of rotations.

This is important because 4x4s have computers that distribute torque between tires as needed to maximize control in precarious driving conditions. The accuracy of that torque distribution depends on the readings of the rotations, so if some tires are rotating at different rates than others, it can cause the computer to distribute the wrong amount of torque—or even initiate a driving mode for the wrong conditions while you're driving on perfectly even asphalt. 

Why Do Some Tires Wear Out Faster Than Others?

Rotating your tires will help ensure both pairs of tires wear out relatively evenly over time. With regular rotations and consistent wear across all your tires, you should be able to replace them all at once at a point when their tread is equally deteriorated. 

But there are other factors at play that could affect some tires more than others, including:

  • Poor alignment
  • Improper inflation
  • Tears, punctures, or other structural damage
  • Aggressiveness of driving and braking
  • Driving conditions
  • Whether tires are on the front or rear axle
  • Using tires that are not the recommended size for the wheels

Which Tires Wear Out Fastest?

Front axle tires wear out faster than rear axle tires on AWD vehicles since the front tires absorb more damage from actions like turning and braking. This is why it's important to have your tires rotated regularly. If you don't rotate your tires, then the front pair will continue losing tread at an even faster rate than your rear tires, requiring you to replace them (and probably both pairs) even earlier.

Does It Save Money To Replace One or Two Tires at a Time?

Graphic illustration of truck with an old set of tires on the rear axle stating that replacing only one or two tires at a time may save you money in the short term but could cost you more in repairs and replacement down the road.

 

In short, it's not usually cheaper to replace only one or two tires at a time for an AWD vehicle. If you think you can save money by trying your luck, you might be able to cut costs in the short term, but the total costs over time can easily overshadow those quick savings. Consider this:

  • Damage to your drivetrain from uneven tread levels could cost a whole lot more than the price of two more tires.
  • You can often get discounts for buying four tires at once.
  • If you choose to replace only one or two at a time, you'll need to shave them down, reducing their life span.
  • You'll have to replace the other two tires at some point, so the risk may not be worth the benefit.

Replacing tires on all-wheel drive vehicles may seem expensive, but repairing mechanical issues to your drivetrain or traction control system is likely even more expensive for any type of vehicle.

Can I Replace Just One Tire on an AWD Vehicle?

Ideally, you should always replace all four tires on an AWD vehicle at the same time—even if only one pair of tires needs to be replaced. However, there can be exceptions to that rule.

Option 1: Patching

If you just installed a new set of tires and run over a nail on your way home, we'll forgive you for not wanting to turn around and buy four more. If you can safely diagnose and patch a tire yourself, this should save you money on replacement. Otherwise, check with a tire pro to see if it's an option for your situation.

Option 2: Tire Shaving

If patching isn't an option—let's say one tire gets gashed to shreds while off-roading—you may be able to replace just the one tire and have it shaved down to the same tread level as its counterparts. The same goes for one pair of tires that wears down faster than the other. Consult a tire specialist to see if shaving the tire (or tires) to match is in the cards for you.

In Summary: All-Wheel Drive Tire Replacement Rules

Graphic showing six rules about the AWD tire replacement myth with illustrations of tires.

We've determined that the AWD tire replacement myth isn't really a myth at all. If you drive an AWD or 4x4 vehicle, we can verify the common wisdom that it's best to replace all four tires at once when you need to replace even just one or two. 

Still, that may not be necessary in all cases. When in doubt, here are a few rules you can refer to:

  • For regular wear and tear, it's best to replace all four tires at once.
  • If one tire is damaged, consider patching it first.
  • If one or two tires need to be replaced out of a new set, you may be able to replace only the damaged ones and shave the tread down to match the others.
  • If you choose to replace only one or two tires at a time, make sure they're the same type as the original ones.
  • To help make sure your tires wear out at the same rate and last as long as possible, rotate them regularly.
  • Always consult a tire specialist to ensure your tire setup is safe.

Remember, safety is more important than saving a little money—and even the little bit of cash you might save upfront when you skimp on a full set of new tires could end up costing you even more down the road. And if you're looking to replace your wheels, check out our tire size calculator to see what size tire you'll need.

FAQs

Do You Need To Replace All Four Tires on a Four-Wheel Drive?

In general, it's a good idea to replace all four tires on a four-wheel drive vehicle at the same time, especially to address regular wear and tear. In some situations, you may be able to replace one or two tires at once and have them shaved down to the same tread level as the remaining tires.

Can You Replace Just Two Tires on an AWD Vehicle?

If you plan to replace just two tires on an AWD vehicle, you'll need to have the new tires shaved down to the same tread level as the remaining two tires. They should also be the same brand and type as the original set. Since shaving reduces a tire's life span, it's not as effective as replacing all four tires at once as a long-term solution.

Where Should New Tires Go on AWD Vehicles?

New tires should go on the rear axle if you're only replacing one pair at a time. This is because your vehicle gets more stability from its rear wheels when driving in dangerous conditions, and newer tires will have better tread than older tires.

Is All-Wheel Drive the Same as Four-Wheel Drive?

All-wheel drive (AWD) automatically switches between driving modes, while four-wheel drive (4WD) consistently distributes power between all four wheels. Since AWD vehicles don't always power all four wheels, they're a little more balanced on paved roads but not as effective off-road or towing as 4WD vehicles.



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