Your tyres are the only parts of your vehicle that actually make contact with the road.
And the way they wear can tell us a surprising amount about what's happening with the vehicle.
Perhaps the inside edge is almost bald while the rest of the tread still looks fine.
Maybe both outer edges are wearing faster.
Perhaps the tread has developed a strange scalloped pattern.
Or you've been told:
“YOUR TYRES ARE WEARING UNEVENLY. YOU NEED AN ALIGNMENT.”
That might be true.
But wheel alignment is only one possible cause of abnormal tyre wear.
At The Cape Brake Co, unusual tyre wear can give us valuable clues about the condition of the:
- Steering
- Suspension
- Shock absorbers
- Wheel alignment
- Tyre pressures
- Wheels and tyres themselves
The important thing is to look at the pattern of the wear and what could have caused it.
WHAT DOES NORMAL TYRE WEAR LOOK LIKE?
Ideally, the tread should wear relatively evenly across the tyre and around its circumference.
Real-world wear will never be absolutely perfect.
Driving style, road conditions, tyre design, vehicle loading and tyre position all influence how quickly a tyre wears.
What we're looking for are significant differences.
For example:
ONE EDGE WORN MUCH MORE THAN THE OTHER
BOTH SHOULDERS WORN
CENTRE OF THE TREAD WORN
PATCHES OR SCALLOPS AROUND THE TYRE
ONE TYRE WEARING VERY DIFFERENTLY FROM THE OTHERS
Those patterns can provide useful information.
WHY ARE MY TYRES WORN ON THE INSIDE EDGE?
Inner-edge tyre wear is commonly associated with wheel geometry.
Excessive negative camber or incorrect toe can contribute to the inside of the tyre wearing faster than the rest of the tread.
But before simply adjusting alignment, we also need to ask:
WHY IS THE GEOMETRY INCORRECT?
Potential factors can include:
- Wheel alignment
- Worn suspension bushes
- Worn ball joints
- Steering play
- Damaged suspension components
- Altered ride height
- Modified suspension
- Vehicle-specific geometry
If something underneath the vehicle is worn or damaged, alignment alone may not solve the problem.
WHY ARE THE OUTSIDE EDGES OF MY TYRES WEARING?
Outer-edge wear can have several possible causes.
Depending on the pattern and vehicle, areas to consider can include:
- Tyre pressure
- Wheel alignment
- Driving conditions
- Cornering loads
- Suspension geometry
Again, one wear pattern doesn't automatically identify one failed component.
We need to look at the tyre and the vehicle underneath it.
WHY ARE BOTH EDGES OF MY TYRE WORN?
Wear concentrated on both shoulders can sometimes be associated with running a tyre at insufficient pressure.
An underinflated tyre can deform differently under load, placing greater stress toward the outer areas of the tread.
But vehicle load and driving conditions also matter.
That's why maintaining the correct tyre pressure is important for more than fuel consumption.
It affects how the tyre operates against the road.
WHY IS THE CENTRE OF MY TYRE WEARING FASTER?
Historically, centre wear has often been associated with excessive tyre pressure.
Tyre construction has evolved considerably, so real-world wear isn't always as simple as one pattern equalling one cause.
Still, unusual centre wear is a reason to check:
- Tyre pressures
- Tyre specification
- Vehicle loading
- Overall tyre condition
The important thing is not to wait until the tyre is worn beyond safe limits before investigating.
WHAT IS TYRE CUPPING OR SCALLOPING?
This is one of the more distinctive wear patterns.
Instead of wearing smoothly around its circumference, the tyre develops alternating high and low areas.
It can look almost as though small sections have been scooped out of the tread.
You may also hear it called:
CUPPING
SCALLOPING
or
PATCH WEAR.
Depending on the cause and severity, the tyre may become increasingly noisy as it wears.
WHAT CAUSES TYRE CUPPING?
Irregular wheel control is one possible contributor.
Potential areas to investigate can include:
- Worn shock absorbers
- Suspension play
- Wheel imbalance
- Tyre condition
- Alignment issues
- Other mechanical problems
A worn shock, for example, may allow the wheel to move less consistently against the road surface.
But:
CUPPED TYRE = BAD SHOCK
is still too simplistic.
We inspect the suspension rather than diagnosing it from the tread pattern alone.
CAN WORN SHOCKS REALLY DAMAGE TYRES?
They can contribute to irregular wear.
The shock absorber's job is to control suspension movement.
If the wheel isn't being adequately controlled, its contact with the road surface can become less consistent.
Over thousands of kilometres, that can contribute to unusual tread wear.
This is why suspension condition affects more than ride comfort.
And once a tyre has developed significant irregular wear, replacing the worn suspension component doesn't magically restore the tyre.
The mechanical cause may be repaired, but the existing tyre wear remains.
CAN WORN BUSHES CAUSE UNEVEN TYRE WEAR?
Yes.
Suspension bushes help locate the wheel relative to the vehicle.
If excessive movement develops in a bush, wheel geometry may change as the vehicle:
- Accelerates
- Brakes
- Corners
- Travels over bumps
A static alignment measurement doesn't necessarily tell the entire story if components are moving excessively under load.
That's why mechanical condition should be addressed before final alignment.
CAN BALL JOINTS AFFECT TYRE WEAR?
Potentially.
Excessive play in a ball joint can allow unwanted wheel movement.
Depending on the suspension design and severity, that may affect:
- Wheel control
- Steering
- Alignment geometry
- Tyre wear
Significant ball-joint play is also a safety concern independent of what it does to the tyre.
So if abnormal tyre wear leads us to discover a worn ball joint, the tyre isn't necessarily the biggest problem anymore.
CAN TIE ROD ENDS CAUSE UNEVEN TYRE WEAR?
Yes.
Tie rods form part of the steering system and influence the direction in which the front wheels point.
Excessive play can affect toe control and steering accuracy.
That can potentially contribute to abnormal tread wear.
And because tie rods are directly involved in setting toe on many vehicles, worn steering joints need to be addressed before accurate alignment.
WHAT IS TOE WEAR?
Incorrect toe means the wheels aren't pointing in the intended direction relative to one another.
Rather than rolling cleanly down the road, the tyre may effectively be dragged slightly sideways as it rotates.
That can create rapid or distinctive tread wear.
In some cases, running your hand across the tread may reveal a feathered or saw-tooth feel.
But don't rely on the hand test alone.
Alignment measurement and mechanical inspection provide much better information.
WHAT IS CAMBER WEAR?
Camber describes the inward or outward inclination of the wheel when viewed from the front of the vehicle.
Too much deviation from the intended geometry can concentrate load toward one side of the tread.
This can contribute to pronounced inner or outer edge wear.
But here's the important part:
Not every vehicle allows camber to be adjusted.
If camber is significantly outside specification on a vehicle without normal camber adjustment, we may need to ask why.
Possible reasons can include:
- Worn components
- Damaged components
- Ride-height changes
- Previous impact
- Modified suspension
- Vehicle-specific issues
CAN A POTHOLE CAUSE UNEVEN TYRE WEAR?
A pothole can potentially affect several things at once.
A significant impact may:
- Damage the tyre
- Bend the wheel
- Affect wheel alignment
- Damage suspension components
- Affect steering components
If you notice unusual tyre wear after a major impact, having the vehicle inspected is sensible.
And if there's a bulge in the tyre sidewall, treat that as a tyre safety issue rather than simply an alignment problem.
WHY IS ONLY ONE TYRE WEARING BADLY?
That's particularly useful information.
If three tyres look relatively normal and one has developed severe abnormal wear, we'd want to investigate what is different at that corner.
That might involve checking:
- Tyre condition
- Pressure
- Wheel condition
- Suspension
- Steering components where applicable
- Alignment geometry
- Shock absorber
- Previous damage
The difference between sides can help narrow the investigation.
WHY ARE MY FRONT TYRES WEARING FASTER THAN THE REAR?
This can sometimes be completely normal depending on the vehicle.
Front tyres may have to deal with:
- Steering
- A significant proportion of braking
- Engine weight
- Drive forces on front-wheel-drive vehicles
Rear tyres experience different loads.
Vehicle design, drivetrain, driving style and tyre rotation practices all influence wear rates.
So:
FRONTS WORE FIRST
doesn't automatically mean something is wrong.
What matters is how they wore.
DOES ROTATING TYRES FIX UNEVEN WEAR?
Rotation can help distribute normal wear across tyres where the tyre type and vehicle manufacturer permit it.
But rotation doesn't repair a mechanical fault.
If one tyre is wearing abnormally because of a worn suspension bush, moving that tyre to another corner simply moves the already damaged tyre.
The cause still needs attention.
WILL WHEEL ALIGNMENT FIX MY WORN TYRES?
Alignment can correct adjustable geometry where required.
But it cannot replace tread that's already disappeared.
If the tyre has severe inner-edge wear, correcting the alignment may help prevent the replacement tyre from suffering the same fate.
It doesn't make the old tyre unworn again.
And if steering or suspension components are worn:
REPAIR THOSE FIRST.
Then perform the required alignment.
DOES CBC DO WHEEL ALIGNMENT?
No.
The Cape Brake Co does not perform wheel alignment in-house.
What we do provide is the mechanical side of the investigation.
We can inspect and repair components such as:
- Control arms
- Suspension bushes
- Ball joints
- Tie rod ends
- Steering components
- Shock absorbers and struts
- Other suspension components
Once the steering and suspension are mechanically sound, wheel alignment can be carried out by an alignment specialist where necessary.
WHY CHECK THE SUSPENSION BEFORE BUYING NEW TYRES?
Because tyres aren't cheap.
If your current tyres have been destroyed by excessive suspension movement or incorrect geometry, fitting a new set without addressing the cause could allow the same thing to happen again.
If there's obvious abnormal wear, it makes sense to ask:
WHY DID THIS TYRE WEAR LIKE THIS?
before simply fitting another one.
CAN MODIFIED SUSPENSION AFFECT TYRE WEAR?
Definitely.
Changes such as:
- Lift kits
- Lowering springs
- Suspension spacers
- Aftermarket control arms
- Different wheel offsets
- Larger wheels and tyres
can change suspension geometry and how the tyre contacts the road.
That doesn't mean modified suspension automatically causes bad tyre wear.
It means the complete setup needs to be considered.
This is particularly relevant to modified bakkies and 4x4s.
WHAT ABOUT HEAVY LOADS AND TOWING?
Vehicle load changes the forces acting through the tyres and suspension.
Regularly carrying heavy loads or towing can affect:
- Tyre temperatures
- Tyre pressures required
- Suspension position
- Wear rates
- Vehicle handling
If the vehicle is primarily used loaded, tell us.
How the vehicle is used matters.
HOW OFTEN SHOULD I LOOK AT MY TYRES?
Regularly.
You don't need workshop equipment to notice:
- One edge disappearing
- Cracks
- Bulges
- Cuts
- Exposed cords
- Very low tread
- Strange scalloped wear
- One tyre looking completely different from the others
A quick visual check can identify a developing problem surprisingly early.
And don't only inspect the outside edge.
INNER-EDGE WEAR CAN BE EASY TO MISS.
A tyre can look perfectly respectable from the outside while the inside shoulder is severely worn.
WHAT SHOULD I TELL CBC?
If you've noticed unusual tyre wear, tell us:
- Make
- Model
- Year
- VIN
- Approximate mileage
- Which tyre or tyres are affected
- Whether the inside or outside edge is worn
- Whether the tread feels scalloped or uneven
- Whether the vehicle pulls
- Whether the steering wheel vibrates
- Whether there are suspension noises
- Whether you've recently hit a pothole
- Whether the vehicle has recently been aligned
- Whether steering or suspension work was recently done
- Whether the suspension is modified
- Whether the vehicle regularly carries heavy loads or tows
Photos of the tyre wear can also be useful.
THE CBC APPROACH TO UNEVEN TYRE WEAR
At The Cape Brake Co, we don't want to look at an unevenly worn tyre and simply say:
“GET AN ALIGNMENT.”
We want to ask:
WHAT DOES THE WEAR PATTERN LOOK LIKE?
ARE THE TYRE PRESSURES CORRECT?
IS THERE PLAY IN THE STEERING?
ARE THE SUSPENSION BUSHES SOUND?
ARE THE BALL JOINTS SOUND?
ARE THE SHOCKS CONTROLLING THE WHEELS PROPERLY?
HAS SOMETHING BEEN DAMAGED OR MODIFIED?
And then, once the mechanical condition is right:
ALIGN THE VEHICLE WHERE REQUIRED.
Because the worn tyre is often evidence of the problem, not necessarily the problem itself.
ARE YOUR TYRES WEARING STRANGELY?
If you've noticed excessive inner-edge wear, scalloping, one tyre wearing differently from the others or you're replacing tyres far sooner than expected, contact The Cape Brake Co.
We can inspect the steering and suspension to establish whether a mechanical fault is contributing to the wear.
Ask the Workshop Assistant or WhatsApp The Cape Brake Co.
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