Perform a road test on the vehicle with the customer. The road test may help to identify many faulty parts such as:

Obvious conditions must be brought to the customer's attention before beginning an alignment. A waddle feeling in the back of the vehicle often indicates the occurrence of a bent rim and/or a belt shift in 1 of the rear tires. Vibration in the steering wheel or in the floor pan is often the result of static imbalance or radial runout of the front tires.