Wheel Alignment

Chapterhahapterpter

Wheel Alignment

Name80 ______Date ______Instructor ______Score ______

Objective: After studying this chapter, you will be able to explain wheel alignment principles. 1. In reference to vehicles, what does the term alignment mean? ______Alignment means to position the four tires so they roll freely and evenly over the road surface.

______2. What does correct alignment provide for a vehicle? ______Automobile safety, sure handling, maximum fuel economy, and long tire life. ______

Wheel Alignment Principles

3. What is the main purpose of wheel alignment? ______To make the tires roll without scufﬁ ng, slipping, or dragging under all operating conditions. ______4. Identify the six fundamental angles or speciﬁ cations needed for proper wheel alignment. ______Any order: caster; camber; toe; steering axis inclination; toe-out on turns (turning radius); tracking ______(thrust line). ______

Caster

5. Steering wheel pull caused by the hump in the center ______crown pull of the road is road _____.

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6. Deﬁ ne positive caster. ______Positive caster tilts the top of the steering knuckle toward the rear of the vehicle and helps keep the ______vehicle’s wheels traveling in a straight line. When you turn the wheels, it lifts the vehicle. Since this ______takes extra turning force, the wheels resist turning and try to return to the straight-ahead position. ______7. It is typical for positive caster to be recommended for ______power vehicles with _____ steering. 8. Negative caster is recommended for vehicles with ______manual _____ steering. 9. Explain how the directional control angle of caster is used to offset the effect of road crown. ______The right front wheel may be set with slightly more positive caster than the left. This counteracts the ______forces caused by the road crown, and the vehicle will travel straight ahead.

______

Camber

10. Deﬁ ne camber. ______Camber is the inward or outward tilt of the wheel and tire assembly when viewed from the front of the ______vehicle. ______11. What are the three reasons for camber? ______Any order: to prevent tire wear on the outer or inner tread; to load the larger inner wheel bearing; to aid ______steering by placing vehicle weight on the inner end of the spindle. ______12. What is the difference between positive camber and negative camber? ______With positive camber, the tops of the wheels tilt outward when viewed from the front of the vehicle. ______With negative camber, the tops of the wheels tilt inward when viewed from the front. ______

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Name ______Toe

13. Toe is determined by the difference in _____ between ______distance the front and rear of the left- and right-hand wheels. 14. Explain the difference between toe-in and toe-out. ______Toe-in is produced when the wheels are closer at the front than at the rear. Toe-in causes the wheels to ______point inward at the front. Toe-out results when the wheels are farther apart at the front than at the rear. ______Toe-out causes the front of the wheels to point away from each other. ______

Steering Axis Inclination

15. Steering axis inclination is always a(n) _____ tilt, ______inward regardless of whether the wheel tilts inward or outward.

16. How does steering axis inclination aid directional stability? ______By helping the steering wheel return to the straight-ahead position. ______

Setback

17. Describe the difference between positive setback and negative setback. ______When setback is positive, the right wheel is farther back than the left wheel. Negative setback is present ______when the left wheel is farther back than the right wheel. ______18. Excessive _____ will cause the vehicle to pull toward ______setback the side with the wheel that is the farthest back.

Toe-Out on Turns (Turning Radius)

19. Explain how toe-out on turns works. ______As the vehicle goes around a turn, the inside tire must travel in a smaller radius circle than the outside ______tire. The steering system is designed to turn the inside wheel sharper than the outside wheel. ______20. _____ built into the steering system produce proper ______Angles toe-out on turns.

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21. With proper tracking, the rear tires follow in the tracks ______front of the _____ tires, with the vehicle moving straight ahead. 22. What can improper tracking cause in a vehicle? ______Poor tracking will increase tire wear, lower fuel economy, and degrade handling. ______

Prealignment Inspection

______(C) 23. All of the following should be checked before attempting wheel alignment, except: (A) worn tires. (B) incorrect cradle alignment. (C) dog tracking. (D) loose wheel bearings.

24. What are possible consequences of improper cradle location? ______Improper cradle location can reduce wheel alignment adjustment range. It can also cause premature tire ______wear, vehicle instability, and incorrect drive line angles. ______

Adjusting Wheel Alignment

______(A) 25. All of the following are common adjustable wheel alignment angles, except: (A) tracking. (B) toe. (C) caster. (D) camber. 26. Explain how caster is adjusted. ______Caster is adjusted by moving the control arm so the ball joint moves toward the front or rear of the ______vehicle. ______27. Camber is usually adjusted after setting _____. ______caster 28. How is toe usually adjusted? ______Toe is adjusted by lengthening or shortening the tie-rods. On most rack-and-pinion steering systems, the ______tie-rod is threaded into the outer ball socket. ______

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Name ______

29. Changing one tie-rod more than the other will ______rotate the steering wheel spokes. 30. What could be the cause of rear wheels failing to track properly? ______Frame, unibody, or rear suspension damage may be the cause. The vehicle might have been in an ______accident that shifted the rear wheels out of place. Worn suspension system bushings can also upset ______tracking. ______

Turning Radius Gauges

31. What do turning radius gauges measure? ______Turning radius gauges measure how many degrees the front wheels are turned right or left. ______

______32. How do you check toe-out on turns? ______To check toe-out on turns, center the front tires of the vehicle on the turning radius gauges. Turn one ° ______of the front wheels until the gauge reads 20 . Then, read the number of degrees showing on the other ______gauge. Check toe-out on turns on both the right and left sides. If toe-out is not within specs, check for ______bent or damaged parts. ______

Caster-Camber Gauge

33. To measure caster with a bubble-type caster-camber ______20 gauge, turn one of the front wheels inward until the radius gauge reads _____ degrees. ______(C) 34. To measure camber with a bubble-type caster-camber gauge, turn the front wheels _____. (A) to the right (B) to the left (C) straight ahead (D) None of the above.

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35. How does a tram gauge work? ______A tram gauge is a metal rod or shaft with two pointers. The pointers slide on the gauge so they can be set ______to measure the distance between the tires. The tram gauge will indicate toe-out or toe-in in either inches ______or millimeters. ______(A) 36. When measuring toe with a tram gauge, the difference between the lines on the front and rear of the tires is _____ actual toe. (A) two times (B) three times (C) four times (D) ﬁ ve times

Alignment Machines

37. What components does the alignment machine include? ______The rack, the console, and related parts. ______38. What does alignment equipment software include? ______Alignment equipment software contains computer instructions, information for using the alignment ______equipment, alignment speciﬁ cations for various makes and models of vehicles, and other helpful ______information. Most software will even give you step-by-step instructions. ______39. What should you check for as you test-drive the vehicle after completing a wheel alignment? ______As you test-drive the car or truck on level pavement, check for a misaligned steering wheel, steering ______wheel pull, and similar troubles. ______

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