The recall population includes select Model Y vehicles and was determined based upon a review of manufacturing and service records from Tesla and the supplier. The front and rear suspension links on Model Y vehicles are attached to the knuckles. The knuckles may not have been manufactured to the correct strength specification, which may cause the knuckle to deform or fracture and may lead the suspension links to separate from the knuckle. During the supplier's manufacture of the knuckles, the quench tank fluid level may not have been sufficient to fully quench the knuckles during the heat treatment process.