Tread with Caution: Types and Causes of Uneven Tread wear Patterns

by Jacksons M. Auto Repair Garage in Northampton

Most new car tyres come with a tread depth of 8mm. It may even be higher on some snow and winter tyres Northampton. With regular use, it is normal for the treads to get shallower and the performance of tyres to alter. When all the metrics are within the recommended parameter, tread wear is expected to happen evenly throughout the tyre body.

However, there are many issues which may cause irregular or uneven tread wear. Since the performance of a tyre is largely dependent on the condition of its tread, it may lead to inferior tyre performance.

Tread depth basics

The 8mm tread depth on new tyres depletes over time. The effect of this depletion is hardly evident as long as it stays above 3mm. As the depth gets lower than that, you’ll start to notice the tell-tale signs on your car’s performance. First of all, there will a noticeable increase in the braking distance.

In a test performed by Bridgestone, tyres with 3mm tread depth took 9.5 metres more for coming to a stop from 80mph compared to ones with 8mm tread depth. The same test concluded that tyres with 1.6mm tread depth (the minimal legal limit in the UK) showed an average braking distance of 18.6 metres. That’s the length of 3 average sedans. Imagine that in city traffic or wintry road conditions!

Irregular tread wear- Types and causes

If the tread wear pattern is uneven, you’ll face several other issues apart from an increased braking distance. Fuel economy, ride comfort, the probability of tyre damage and steering response are all affected by irregular tread patterns. There may be different types of uneven tread wear patterns, some of which are mentioned below.

Scalloping
Feathering
One or both shoulders
Centre rib
Lateral
Spot shoulder
Patches

The most common causes of these types of tread wear are-

Improper inflation

Car manufacturers recommend the perfect inflation pressure after taking into account various factors such as load distribution, braking and steering forces, and cornering angles. All of these have a direct bearing on a tyre’s tread wear rate and pattern. Both under and over-inflation may cause irregular tread wear.

In the case of under-inflation, the load will be concentrated on the two shoulders of a tyre, leading to excess tread wear on those parts. On the other hand, when a tyre is under-inflated, the centre rib handles most of the load, causing tread wear along the centre of that tyre.

Solution:

Check your tyre inflation pressure at least once a week.
Maintain proper inflation at all times.
Rotate tyres every 6 months.

Wheel alignment and balancing

When your car’s tyres are at a disproportionate angle, it leads to irregular tread wear. The contact patch of a tyre is altered when it is out of alignment, leading to accelerated wear on the side which is more in contact with the tarmac.

Out of balance wheels present a slightly different problem. It leads to the concentration of mass on specific spots and causes increased tread wear on those spots. You’ll notice patchy tread wear if your wheels are unbalanced.

Solution:

Check your tyre’s alignment and balance when you go for tyre rotation, and recalibrate them as necessary.

You may avail these services at professional auto workshops like Jackson’s MOT Centre. Along with performing wheel alignment and balancing, they also do essential car repairs like clutch, engine and brake repair Northampton.