There are very few situations as serious as being forced to buy a new set of tires, just because a particular part of the tire has worn out faster than the remaining tread. This can be an expensive problem to deal with when tire prices are constantly increasing.
Few tire wear problems are as important as inner tire wear. Many drivers face this same problem every year, and many need to consider the root cause of their dilemma.
Fortunately, the cause of inner tire wear is rarely difficult to cure and can be quickly treated with a little knowledge. Read on to learn more about the causes of tire wear on the inner rim and how to fix these problems.
Related: 5 reasons to use OUTDOOR tires
What causes indoor tire wear?
Tires wear on their inner edges for many reasons. However, most of them involve basic steering and suspension problems. When these issues are properly addressed, this annoying uneven wear pattern usually goes away.
These are the most common culprits of tire wear.
#1 – Incorrect tilt angles
Camber is the narrow measurement of the tire, inward or outward, when viewed from the front or rear. A positive camber describes a tire that is tilted outward at the top, while a negative camber describes a condition in which a tire faces the vehicle. In the case of internal tire wear, the fault is usually a negative cam.
When a vehicle has a negative camber, you will usually notice that its front tires are wearing inward, as this part of the tire makes more contact with the road surface. The same can also be said when someone notices that there is a rear tire on the inside edge when talking about a vehicle with independent suspension on all 4 wheels.
See also: Are Wheel Spacers Safe?
#2 – Incorrect toe angle
Toe-in is defined as the angle of a vehicle’s tires relative to each other or the centerline of a vehicle. This angle can be observed by standing in front of a vehicle, and looking at the leading edge of both tires.
A “pinch” is clearly a condition where the two tires appear to be pointing toward each other. In contrast, “toe-in” is evident when the tires appear to be facing outward.
A vehicle with a significant amount of toe-in will often show accelerated wear on the inside edge of its tires. This is because the inside of each tire is stuck to the pavement to some extent.
As a result, the tread compound wears prematurely on the part of the tire that was forced to absorb most of the friction.
Also read: What is a scalloped base?
#3 – Worn kneecaps
Another major cause of uneven tire wear is worn ball joints. In the case of accelerated internal tire wear, worn lower ball joints are usually the culprit.
Ball joints use a ball and socket type design to attach a vehicle’s control arms to its steering knuckles. When new, a ball joint serves this purpose, with little to no play in its ball joint and socket.
As a kneecap begins to age, normal friction causes the kneecap to loosen and warp and show some free play. This free play allows involuntary outward movement of the steering wheel itself and, therefore, has the same effect on its corresponding wheels.
As a result, worn lower ball joints can change the lean angle of a vehicle, to the point of causing wear on the inside of the tires.
See also: The causes why a car pulls to one side when braking
#4 – Crushed Worn Control Hands
The control arms act as a connection between the vehicle’s frame and the steering knuckle. The upper and lower control arms are equipped with rubber or elastomer bushings at their pivot points along the vehicle frame. The purpose of these bushings is to prevent excessive free play which could have a negative effect on camber angles.
As control arm bushings age, they slowly begin to deteriorate. This deterioration allows the control arm joint to the vehicle frame to have too much play, which will change the camber configuration of the corresponding wheel end.
As a byproduct, pavement wear is unlikely to occur uniformly and often erodes the inner tread of tires.
#5 – Worn or damaged suspension components
A vehicle’s struts and springs do more than absorb road vibrations and impacts associated with a pothole. These components also play a vital role in maintaining the basic ride height of the vehicle.
This set ride height directly affects the vehicle’s lean angles, which can result in less than satisfactory tire wear when disturbed.
Unfortunately, as the vehicle ages, the springs tend to sag, effectively lowering the vehicle’s ride height. Additionally, significant impacts of any type can cause the strut tower to tilt, which may result in an out-of-spec tilt adjustment.
As a result, uneven tire wear often occurs. Correcting these problems usually requires replacing components or shimming the affected springs.