What alignment angle needs to be checked after replacing an idler arm?

After replacing an idler arm, it is essential to check the toe alignment angle. The idler arm is a crucial component of the steering linkage that helps to maintain the proper geometry of the steering system. When it is replaced, it can alter the relationship between the vehicle's wheels, particularly affecting the toe, which is the angle at which the wheels point in relation to the centerline of the vehicle.

Checking the toe alignment ensures that both front wheels are parallel or properly angled towards or away from each other. If the toe is not correctly adjusted following the installation of a new idler arm, it could lead to uneven tire wear, poor handling, and potential safety issues. Therefore, ensuring that toe is within specification after such a replacement is crucial for maintaining proper vehicle performance and safety.