My first question is is it neccasary to get an ailignment after a tire rotation? I ask because my civic has hit 22K miles and I plan on rotating the tires by myself soon. How neccassary is it to get an ailignment? I'm also curious as to what the difference is between an ailignment and balancing. All I know so far is that one costs more then the other. Thanks in advance to whoever can answer this.

 

Balancing a tire consists of adding weights to the wheel inorder to balance the rotation of the tire due to uneven tire wear or things of that nature.
http://www.discounttire.com/dtc/brochure/i...tireBalance.jsp

An alignment is adjustments in the angles of the wheels so that they are perpendicular to the ground and parallel to each other. The purpose of these adjustments is maximum tire life and a vehicle that tracks straight and true when driving along a straight and level road.
http://www.discounttire.com/dtc/brochure/i...skAlignment.jsp

 

If you have stock Potenza S-02s (or similar staggered tires), you can NOT rotate the tires unless you dismount the tire, spin it around and reinstall it. They have a directional tread and are different sizes front and rear.

Alignment is when all steering angles are set to OEM spec, or within bounds, not necessarily perpendicular to the ground and parallel to one another. You have camber and toe adjustments front and rear, and a caster adjustment up front. Wheel alignment is intended to provide a safe, stable ride and/or a performance ride, plus extended tire life (even tire wear) and to prevent dogtracking or a pull.

The alignment deals with your track bars, strut bars, tie rods, and all the mechanical underpinnings of the suspension, whereas wheel balance deals strictly with the tire/wheel assembly. You can balance a tire on a single plane or a double plane. The single plane tire balance (static imbalance) will help eliminate a tire wobble (similar to wheel hop or axle bind), and a dual plane tire balance (dynamic imbalance) will eliminate the tire wobble and a tire shimmy. The static imbalance is when the wheel is not balanced along the centerline of the wheel; the dynamic imbalance is when the wheel is not balanced on either side of the wheel centerline.

Generally, a wheel alignment is more expensive than a tire/wheel balance because it's simply more work, more time, and thus more money.

 

Unless I see uneven tire wear I don't have my cars aligned. Unless I feel tire related vibration I don't have my tires balanced.

Some say that you should align you car after the purchase of new tires, to ensure that your car's alignment will not cause premature wear on your new tires. I figure that if the old tires did not wear unevenly then the new tires will not either, so I don't get alignments then either.

One reason to get an alignment is to make sure that your suspension parts are not worn out. The alignment guy will tell you if you need tie rods ends, ball joints or if your boots are cracked or if your steering rack is leaking.

--Mike