ASE A4 study guide
ASE A4 · Work through your exam, one topic at a time.
ASE A4, Suspension and Steering, is one of the automobile and light truck certification tests administered by the National Institute for Automotive Service Excellence (ASE), an organization that certifies automotive service professionals across dealerships, independent shops, fleets, schools and colleges. ASE certification is a voluntary, industry-recognized credential meant to show verified technical knowledge rather than simply years on the job. The ASE A4 study guide has 5 sections and about 1,675 words.
01Steering Systems
Steering questions usually begin with identifying the system installed. Recirculating-ball gears (common on older RWD cars and trucks) use a worm, ball nut, and sector shaft with a parallelogram linkage: pitman arm, center link, idler arm, and tie rod ends.
354 words, about 2 min02Suspension Systems
Suspension questions test whether you know where the weight goes. On a MacPherson strut, the strut carries the spring load and the lower ball joint is typically load-bearing (axial).
346 words, about 2 min03Wheel Alignment
Camber tilts the tire top in or out; too much negative camber wears the inner shoulder. Caster is the steering axis tilt and provides directional stability and returnability - it does not wear tires but causes a pull toward the side with less positive caster.
317 words, about 2 min04Wheels and Tires
A size like P225/60R16 98H decodes as passenger tire, 225 mm section width, 60 aspect ratio, radial construction, 16-inch rim, 98 load index, and H speed rating. Replacement tires must meet or exceed the OE load index and speed rating.
330 words, about 2 min05Miscellaneous (Related Suspension and Steering Diagnosis and Repair)
The miscellaneous domain rewards a disciplined road test. Vibration that changes with vehicle speed but not engine speed points to tires, wheels, or bearings; vibration tied to engine RPM in a given gear points to the driveline.
328 words, about 2 min