Tire Camber Wear

subaru
tires
forester

#1

I recently noticed camber wear on the front driver side tire of my car.

I have seen multiple explanations for cause of camber wear (i.e. suspension issues and alignment) but I’m curious if the problem could be caused by the fact that my wife and I both ride on the driver side of the vehicle - usually with me in front and her in back with two infants.

I’m a pretty big guy and my wife isn’t petite so I imagine it’s a sizable imbalance.

I did notice a couple months after purchasing the vehicle that the front, passenger side tire is a different tire than the others (though the same size).

Any thoughts on theory that 400 pounds more on the driver side could cause the camber wear?


#2

Interesting question.
Is the wear on the outside edge or the inside edge? How significant is the wear difference between the inside edge and the outside edge?

Your suspension is designed such that as the front wheel travels up or down from its static position, it leans inward (known as “negative camber”). It does this to prevent “scrubbing”, which is moving back and forth. Because of the way the parts move through their arcs, if they were not leaned in during the movement the tires would move back and forth, causing constantly changing distances between the wheels (the “track”). As you can surmise, this would cause weird handling and erasing of the tread.

It is entirely possible that with that much weight routinely on one side the wheel on that side could be slightly negatively cambered, causing uneven wear. I guess the only way to really find out is at an alignment shop.


#3

Thanks for the response. I’ll take it to an alignment shop but was curious about the weight distribution and found nothing online regarding this though I know we’re not the only parents who often have this seating configuration.
I haven’t noticed anything odd about the handling.
The wear is on the outside edge and is readily visible, which is to say, significant compared to the three tires of the same age/mfg.


#4

When you’re there having it aligned, present the question to them. If they’re willing to make such a measurement (loaded vs. unloaded) post back with the results. I myself would be curious as to whether that much imbalance could affect canber enough to show up as wear.

By the way, I would have expected the wear to be on the inside edge. I’m willing to bet now that you have a simple out-of-alignment condition, perhaps even caused by worn suspension components.


#5

I agree, with the wear on the outside edge loading is not the likely cause. But toe-out can cause excess wear on the outside of the tires which could, like negative camber, be caused by worn suspension/steering parts as mountainbike mentioned.


#6

It’s extremely unlikely that the weigh distribution has anything to do with this.
While there are things about the car that are not presented (mileage, car history as to being purchased new, collision damage, etc.) my gut feeling is that there could be a suspension issue related to a collision, curb strike, or large pothole.
Wear on the outside edge of the tire points to too much positive camber.

If the LF is struck hard in one of the above scenarios this can cause the lower control arm to get tucked back under a bit, for want of a better phrase. When this occurs it brings the top of the tire out and the bottom of the tire in, creating more positive camber. Quite often this is not something that one could determine by eyeball.

You might have the car put on the alignment rack and pay close attention to the camber reading on the LF. It’s always possible that too much toe-in could cause this but both wheels are generally affected by that. Hope that helps.