When you take your car in for a wheel alignment, the technician isn't just spinning wrenches under the car. They're adjusting specific suspension components to ensure your tires meet the road at the correct angles. But what exactly gets aligned? Many drivers assume the entire suspension is tweaked, but that's not the case. An alignment focuses on three key angles: toe, camber, and caster. To adjust these, the technician works on parts like tie rods, control arms, and sometimes struts. Let's break down exactly which parts of your suspension get aligned and how they affect your driving.
Understanding the Three Alignment Angles
Before diving into the parts, it helps to understand what the alignment is trying to achieve. The goal is to set the wheels parallel to each other and perpendicular to the road. This reduces tire wear, keeps the car tracking straight, and improves handling. The three angles are:
- Toe: The angle of the tires relative to the centerline of the car, viewed from above. Toe-in means the front of the tires point inward; toe-out means they point outward.
- Camber: The tilt of the tire when viewed from the front. Negative camber means the top of the tire leans inward; positive camber means it leans outward.
- Caster: The angle of the steering pivot axis when viewed from the side. It affects steering feel and stability.
Each angle is adjusted using specific suspension parts. Some are adjustable by design; others require aftermarket components.
Parts That Get Adjusted During a Standard Alignment
A standard alignment typically addresses the front suspension, though some vehicles also have adjustable rear suspension. Here are the primary parts the technician will manipulate.
Tie Rods (Toe Adjustment)
The most common adjustment is toe, and that's done through the tie rods. Tie rods connect the steering rack to the steering knuckles. By loosening the lock nuts and turning the tie rod sleeves, the technician can lengthen or shorten the tie rods, pushing or pulling the front of the tires to achieve the correct toe setting. This is a simple but critical adjustment. If your steering wheel is off-center or the car pulls to one side, toe adjustment via the tie rods is likely the fix.
Control Arms and Eccentric Bolts (Camber Adjustment)
Camber adjustment often involves the lower control arms or upper control arms, depending on the suspension design. Many modern vehicles use eccentric bolts or cam bolts at the mounting points of the control arms. By rotating these bolts, the technician moves the top or bottom of the tire inward or outward to adjust camber. On some vehicles, especially those with MacPherson struts, camber is adjusted at the strut-to-knuckle connection or by moving the strut's upper mount. If your car has excessive tire wear on the inner or outer edge, camber adjustment is likely needed.
Struts and Shock Absorbers (Caster and Camber Combinations)
In vehicles with MacPherson struts, the strut assembly also plays a role in alignment. The strut mounts at the top (often with slotted holes or eccentric mounts) can be adjusted to change camber and sometimes caster. Additionally, the strut's relationship to the knuckle can be adjusted with camber plates or aftermarket bolts. Caster is typically adjusted by moving the lower control arm forward or backward, or by using eccentric bushings. However, many vehicles have fixed caster, so adjustments are limited unless aftermarket parts are installed.
Rear Suspension Adjustments
Many modern cars have independent rear suspensions with adjustable components. The same principles apply: toe and camber can be adjusted using tie rods (for toe) and camber arms or eccentric bolts (for camber). If your rear suspension is a solid axle, alignment adjustments may be minimal or require shims. Always check your vehicle's specifications.
What Parts Are NOT Typically Adjusted?
It's important to know what an alignment does not involve. The technician will not replace parts during an alignment; they only make fine adjustments to existing components. Also, alignment does not fix worn-out suspension parts. If your ball joints, bushings, or wheel bearings are loose, the alignment won't hold. The technician usually inspects these parts before starting. Common non-adjustable parts include:
- Springs: Not part of alignment adjustments.
- Shock absorbers: Their damping is not changed, but they may need to be positioned correctly.
- Sway bars: Usually not adjusted during alignment.
When Alignment Is Not Enough: Things That Need Repair First
If your vehicle has sloppy handling or uneven tire wear, an alignment alone might not solve the problem. Worn suspension components can cause alignment angles to shift, making adjustments impossible. Before an alignment, a good shop will check:
- Ball joints: If they have play, camber and caster won't be accurate.
- Control arm bushings: Worn or cracked bushings allow movement that throws off alignment angles.
- Steering rack or tie rod ends: Loose components affect toe adjustment.
- Wheel bearings: Excessive play can mimic alignment issues.
Always address these mechanical problems before scheduling an alignment. Otherwise, you're wasting money.
Practical Recommendations for Getting the Right Alignment
When you visit an alignment shop, don't just drop off the car without a conversation. Ask the technician to print a before-and-after alignment spec sheet. This shows which angles were adjusted and what the final readings are. If your vehicle has abnormal tire wear, point it out so they know what to prioritize.
Also, understand that not all cars have the same adjustment range. Some older vehicles or economy cars may have limited camber and caster adjustability. In such cases, you may need aftermarket adjustment kits (e.g., camber bolts, adjustable control arms) to correct severe misalignment. Discuss this with a professional.
Finally, alignments are not a one-time fix. If you hit a big pothole or curb, the alignment can be knocked out of spec. Hitting a deep pothole can bend a tie rod or control arm, requiring replacement before alignment. Regular alignments (every 12,000 miles or once a year) help protect your tires and suspension.
Final Recommendation
The parts of your suspension that get aligned are primarily the tie rods for toe, and the control arms or struts for camber and caster. But remember: an alignment only adjusts these parts—it doesn't fix worn components. If you suspect an alignment issue, have a professional inspection first. Check your owner's manual for alignment specifications, and always request a detailed printout after service. This will help you understand what was adjusted and why. By knowing which parts are involved, you can better maintain your car's handling and tire life.