Having your vehicle's wheels aligned is very important, as improper alignment can cause drag, pulling, skidding when you brake, and a host of other problems that make it difficult if not downright dangerous to drive. However, an improper wheel alignment is not to blame for all the troubles you may be having with your vehicle, so it's important to separate the fact from the fiction when it comes to getting an alignment and ensuring your vehicle is in good mechanical shape.

When the vehicle bounces

If the vehicle bounces excessively over bumps or seems to bounce forward from the back end when you apply the brakes, this is usually a problem with the shocks and not an alignment issue. The shocks should be absorbing the movement of the tyres when you drive over bumps; when they wear out, you'll feel that bouncing even if the tyres are perfectly aligned.

Drag when accelerating

If your car drags or pulls to one side while you're driving down the road, this can be an issue with poor alignment. However, if the car seems to actually drive straight, but only drags or resists when you release the brake pedal and hit the accelerator, this is often a problem with the brakes. The brake callipers and pads may not be releasing the wheel's rotors properly so that the car hesitates when you try to accelerate. Take note of exactly how the vehicle drags, as this will indicate if the car needs an alignment or new brakes.

Vibrations

In some cases, poor alignment can cause the wheels to vibrate as they struggle to rotate smoothly and evenly. However, there are also many other causes of vibrations in the steering wheel, including brakes that aren't releasing, as mentioned above. Loose lug nuts can cause a tyre to vibrate, as it's not sitting securely on the rotor. It's good to get these issues checked before assuming that a wheel alignment will automatically fix vibrations in the steering.

Mismatched tyres

Tyres on a vehicle should all match; unevenly sized tyres can cause pulling and dragging, and excessive wear and tear on the steering column and other components. Having the tyres aligned won't compensate for mismatched tyres and won't prevent this pulling and dragging. In some cases, tyres may be of the same size, but one has worn down more than the others, and the tyres need to be balanced; this means adding a small bit of weight to the worn tyres, but doesn't refer to actually aligning them.