Car alignment (also known as wheel alignment) ensures your wheels are correctly angled according to manufacturer specifications. With proper alignment, you’ll enjoy better fuel economy, more accurate handling, reduced tire wear, and straight driving.
While professional alignment is common, those with mechanical skills and the right equipment can attempt a basic at-home alignment. Here’s a guide to doing it safely and accurately.
Types of Wheel Alignment
The two most common forms of wheel alignment are two-wheel and four-wheel. Although four-wheel alignment is standard, two-wheel alignment is sometimes preferred.
In FWD vehicles, the type of alignment primarily depends on the age of the vehicle. Older vehicles with solid, non-adjustable rear axles are best aligned using a two-wheel alignment, also known as a front-wheel alignment.
However, most modern FWD cars feature a lightweight design for the rear axles and suspension system. This makes the wheels more susceptible to misalignment, usually necessitating a four-wheel alignment.
Two-wheel alignment: Only the front wheels are adjusted in a two-wheel, or front-wheel, alignment. This type of alignment will prevent your car from pulling and reduce uneven wear on your front tires.
A two-wheel alignment is typical for trucks and older cars equipped with solid rear axles. While easier to do at home, a two-wheel alignment may sacrifice accuracy compared to the more common and precise four-wheel alignment.
Four-wheel alignment: As the name suggests, all four wheels are adjusted in this alignment, also called an all-wheel alignment. It corrects issues such as pulling and crooked steering, and it minimizes uneven tire wear.
Four-wheel alignment is standard in most modern cars for greater accuracy. It requires precision tools, which makes it somewhat more challenging than a DIY two-wheel alignment. Nonetheless, you can still carry out a four-wheel alignment from the comfort of your own garage.
Tools and Supplies You’ll Need
- jack and stands
- lug wrench
- measuring tape or alignment gauge
- straight edge or string
- chalk or painter’s tape
- owners’ manual
Step One: Prepare Your Workspace
Make sure the car is parked on a flat, even surface. Verify that the tires are inflated properly and that there is no extra weight in the vehicle. For safety, set the parking brake and chock the wheels before working on the vehicle.
During adjustments, wheel chocks should be used. If adjusting the front wheels, place chocks behind and in front of the rear tires. If adjusting the rear wheels, place chocks behind and in front of the front tires.
Having the car on level ground during a wheel alignment is crucial. When measuring camber or toe, a vehicle supported by jack stands will throw your measurements off because the suspension isn’t loaded. It’s best to only jack up the car to access camber bolts, control arms, or tie rod locking nuts.
Step Two: Check and Adjust the Camber
When looking at a car from the front, camber is the inward or outward tilt of its wheels. Too much negative camber (wheels tilt inward) or positive camber (wheels tilt outward) affects tire wear and steering response.
Camber is measured by placing a straightedge vertically against the wheel and measuring the distance from the straightedge to the tire’s top. See how this measures up against your manufacturer’s specifications.
On some vehicles, you can adjust the camber via bolts. Others, however, need aftermarket solutions or professional assistance. If the camber is not adjustable, document it and get professional help.
Step Three: Check Toe Angle
From an overhead perspective, toe describes the inward or outward angle of the tires. When the front tires angle toward each other, it’s called toe-in; when they angle away, toe-out.
To measure toe, check how much the front edges of your front tires point inward or outward compared to the rear edges.
In most basic driveway toe checks, you only need to measure and adjust the front toe. That being said, the steps for measuring rear toe are the same, only you would mark and measure the rear wheels to find rear toe. Keep in mind the term rear distance doesn’t refer to the rear tires, but the distance measured at the rear of two tires. Likewise, front distance refers to the measurement taken at the front side of the tires.
- Mark each front tire by place a mark on the inner sidewall of both front tires at the same height, ideally on the centre line of the tire as viewed from the side.
- Measure the distance between the marks straight across the front of the tires. This measurement is called the front distance.
- Roll the car forward slightly, rotating the wheels 180 degrees. The same marks made in step one should rotate to the back side of the tires.
- Now measure the distance between the same marks, but across the rear of the tires. This is the rear distance.
If the front distance is smaller than the rear distance, the tires are toed in, i.e., they point inward.
If the front distance is larger, your tires are toed out, i.e., pointing outward.
To change the toe setting, loosen the lock nuts on the tie rods behind the wheels, rotate the rods to adjust wheel angle, and retighten the nuts when the correct measurement is reached. Following adjustment, measure again to confirm the front distance and rear distance measurements across two tires are equal.
Step Four: Test Drive and Fine Tune
Ensure the steering wheel is straight before finalizing toe adjustments. Uneven toe adjustments can result in a misaligned steering wheel afterward. On a level surface, the steering wheel should remain straight when driving the vehicle forward.
Lower the vehicle, remove the wheel chocks, and test drive it briefly. Notice how the car handles. Does it still veer to one side? Is the steering wheel centred? Are the tires quiet and smooth? If you notice issues, recheck your measurements and fine tune.
Performing your own car alignment requires precision and caution. Persistent drifting, uneven tire wear, or alignment uncertainty warrants a visit to a professional alignment shop.