Wheel Alignment: How to Adjust Camber

Except for the actual construction of the tires, wheel alignment is the most influential factor on the lifespan of your tires. One of those measures, camber, refers to the tilt of the wheel—specifically, how many degrees "off-vertical" the tilt is.

Positive Camber vs. Negative Camber

When looking at the vehicle from the front or rear, you will see the profile of the wheel and tire. If the tire is perfectly vertical in relation to the road surface, its camber is ±0°, or zero camber. If the top of the wheel is tilted towards the vehicle, it has negative camber. If the top of the wheel is tilted away from the vehicle, it has positive camber.

Positive camber and negative camber affect the vehicle in different ways.

Zero static camber would result in even tire wear, but would likely impact cornering performance, because dynamic camber varies, depending on vehicle speed, roll, and G-forces. Because of this dynamic change, most street vehicles have at least some negative camber, even more for performance cars. The harder you take a turn, the more the tire rolls, so zero camber becomes positive camber, resulting in poor traction and handling. Negative camber on the outside wheel comes closer to zero camber, planting more of the tread into the road surface for superior traction.

Sports cars may have a lot of negative camber on all four wheels, up to for better cornering. Formula 1 cars may run greater than -3.0° camber on the front tires, and -1.0° camber on the rear tires, which gives them straight-line acceleration and better cornering traction. NASCAR and other oval racers might have up to -3.0° camber on the right side and +3.0 camber on the left side, because G-forces are always pushing them to the outside of the turn. They get worse straight-line stability and way better cornering, but only if they turn left.

Positive camber is almost never found on street vehicles, as it impacts vehicle stability and handling. Dedicated off-road vehicles and agricultural vehicles have positive camber because it reduces steering effort.

When to Adjust Camber

Camber problems usually show up as handling or tire wear problems. Usually, all four wheels will feature some negative camber, and a vehicle will tend to pull to the side that has the most positive camber. For example, if the front wheels are at -0.5° L and R ±0.0°, the vehicle would likely pull to the right. Excessive camber either way will cause excessive and abnormal tire wear. Negative camber wears the inside edge of the tire, while positive camber wears the outside edge of the tire. In conjunction with toe angles, some high-negative camber vehicles don’t experience this wear characteristic, though.

As mentioned, camber angles are set to balance traction and wear. Camber may need to be adjusted if your usage scenario demands better cornering performance. Abnormal tire wear, pulling, or poor directional stability may also stem from camber angle problems. Of course, we left out tuner cars and Bosozoku cars, which may feature custom lowered suspensions and extreme camber angles. Such extreme camber, up to -30°, are purely for aesthetic reasons, but essentially useless in actual performance scenarios.

How to Adjust Camber

Usually, camber is only measured as part of a four-wheel alignment. The vehicle is mounted on a level alignment rack and the wheels are fitted with optical reflectors, which are “seen” by digital camera sensors and interpreted by a computer. Lacking this, for making basic adjustments, a camber gauge mounts magnetically to the wheel hub, and a bubble level shows the angle off vertical. There are several methods to adjust camber, depending on the vehicle and its suspension. Stock suspensions may feature cam bolts, eccentric washer bolts, turn-buckle joints, or shim adjustments.

Cam bolts and eccentric washer bolts are similar, in that the off-center bolt can be used to push or pull the suspension component in or out. On double-wishbone and multi-link independent suspensions, these may be used to move the upper or lower control arms. On McPherson strut suspensions, they may be used to adjust the lower control arm or the steering knuckle.

Turn-buckle joints are usually limited to rear multi-link suspensions but are sometimes found on front wishbone suspensions. Shim adjustments are usually found in front suspensions but can be in almost any application. To correct solid axles on rear suspensions, the aftermarket offers shims that offset the entire wheel bearing and hub assembly. Finally, some aftermarket ball joints feature an eccentric mount, allowing for adjustability.

The last adjustment method, adjustable shock mounts or caster/camber plates, is usually limited to the aftermarket. By cutting out the OEM shock mount, and installing the plate, users have more control over camber angles, great for tuners and racers to get even more camber for better cornering. As they adjust in minutes, one can even set a racing angle for the track, then a driving angle to get back home.

Unless you’re a tuner, the best way to ensure consistent performance, handling, and tire life is to bring your vehicle to a competent alignment shop. After making sure all joints are within tolerances, a computerized four-wheel alignment will keep all your angles within specification, caster, camber, toe, and more.