AXL Alignment

AXL measures wheel alignment with an iPhone. Hold the phone flush against each wheel, and against matching spots on the chassis, and AXL reads toe, camber, and the car’s centerline. How to measure Work in this order: centerline, then toe, then camber. For the centerline, place the phone on a straight part of the rear quarter panel, or another straight chassis feature. Repeat the same kind of spot on the other side. Keep the top of the phone toward the front of the car and do not turn it around. Do not measure on a door or a gas cap. For toe and camber, press the phone completely flush against the face of the wheel, along the top edge, off any curves or contours. For toe, the screen faces the sky. For camber, stand the phone upright with the screen toward the rear of the car. Use the volume-button edge on the right side of the car and the power-button edge on the left so the top of the phone still points forward as you walk around. Hold still. AXL captures the angle once the phone has settled, then moves you to the next wheel. A pass ends on its own when all four wheels are done. Centerline and toe should be taken in the same visit so they share the same direction reference. AXL is most accurate with a completely flat-sided phone case, or with the 3D-printable case file that will be available from our website. What you get You see each wheel’s toe and camber, total toe for the front and rear axles, and how the rear axle sits on the car (thrust versus the chassis). Positive toe means the fronts of the wheels point toward each other. Negative camber means the top of the wheel leans in toward the car. The 3D view draws those angles larger than they are so small readings are easy to see. The numbers on the cards are the real measurement. Teal is the toe line, orange is camber, white is the chassis centerline, and gray is the thrust line. Front and rear total toe are colored for a typical passenger car: green within 0.20° of straight, yellow up to 0.50° if it should be adjusted, and red beyond that, where the angle is large enough to wear the tires. Toe-in and toe-out use the same colors. This is not a factory specification for a particular vehicle. Vehicles and history Save a test to a named car, add an optional note such as “before adjustment,” and open any previous test later. With two or more saved tests you can compare them: axle totals, chassis, and every wheel, with the change between any two visits. AXL is a measurement tool for seeing how the wheels sit on the car. It does not replace a shop alignment rack, and it does not claim a precision that has not been checked against one.