Be honest, before you lowered your truck, you never gave the alignment "thing" a second thought. You’re now older and wiser, however, and realize you must seriously consider this important issue before you choose your method of lowering, especially if the vehicle is not just a show truck but serves as your daily driver. Improperly aligning your truck can cause serious handling problems, as well as uneven, premature wheel and tire wear.
Often people with lowered trucks assume they are experiencing “bump steer,” a phenomenon that occurs when the wheels steer themselves without input from the steering wheel. However, the most likely culprit is often just alignment. Modern trucks and SUVs have independent front suspension (“IFS”) and the wheels have the ability to react independently by design.
Let’s begin this tutorial by defining the fundamentals of alignment, especially where it pertains to lowered trucks. There are three big adjustments in your front end that, when set properly, will result in miles of driving pleasure – CAMBER, CASTER, and TOE. If any of these three are not set correctly, you won’t be a happy camper. Let’s explore this alignment trifecta:
CAMBER: Simply put, camber is the angle of the wheel, measured in degrees, when viewed from the front of the vehicle. If the top of the tire is leaning in (towards the frame) then you have negative camber. If the top of the tire is leaning out (away from the frame), you have positive camber. The camber angle in image to the right is 0.
CASTER: When you turn your steering wheel, your wheels turn either left or right and this pivot is known as caster. It is the angle of pivot viewed from the side relative to straight up and down. If this pivot angle is leaning toward the back of the car it is positive caster, and, of course, if the angle is rotated toward the front of the truck, it is negative caster.
So what happens if caster is out of alignment? You would notice problems in straight-line tracking or if it was different from side-to-side, the truck would pull to the side with less positive caster. If both sides are equal but too negative, the steering will feel light, the truck will wander and won't drive straight. If both sides are equal but too positive, the steering can be heavy.
Some people argue, however, that you cannot have too much positive caster. Remember there are no absolute right numbers when it comes to aligning your truck. If you are the spirited driver, you could benefit from some of the handling properties of positive caster, including improved tire contact patch during cornering, turn-in response, directional control, as well as steering self-center and steering feel.
In fact , if you are trying to fine-tune your alignment , it is better to adjust caster than camber. Why you ask? Let's look:
TOE IN/OUT: If you are doing your own alignment or just getting it close before you take it in, always make the toe adjustment your last one. The toe setting is used to compensate for the suspension bushings compliance and to reduce tire wear. On rear-wheel drive trucks, they push the front-end down the road, causing the control arms to “deflect” rearward against their bushings. Because of this, most rear-wheel drive vehicles use some positive toe-in, which allow the wheels to run parallel to each other at highway speeds.
Toe can also be used to affect your truck’s handling. Increased toe-in will typically result in reduced oversteer and improve high-speed stability, but too much and you get an unresponsive, thick feeling.
Increased toe-out, on the other hand, reduces understeer, and improves “turn in” when cornering. Excessive toe-out makes the truck feel “nervous” and twitchy, as if it’s lacking directional stability. Racecars are generally set with toe-out, as they are willing to sacrifice straight-line stability for a sharper turn-in to the corners. For street guys, a little toe-in is probably the best choice.
Okay, now that you know the lingo, let’s get into the 5 cardinal rules of lowered truck alignment:
FIRST LAW OF ALIGNMENT: Find a mechanic who understands lowered suspensions. It's unbelievable how many mechanics will tell you, “ Sorry, dude. I can’t align this thing because it's been lowered.” Hogwash! Every CALMAX Suspension system can be set to factory alignment no matter how low it is. If this happens to you, run like the wind to another alignment shop that actually understands this basic principle.
SECOND LAW OF ALIGNMENT: When you lower a truck, you cause negative camber. When you lift a truck you cause positive camber. It’s that simple, and this is why the way you lower is so important.
Cutting, heating, or even using engineered lowering coil springs will cause negative camber every time and you need the ability to adjust the camber enough to offset this. Camber adjustment takes place with the upper control arm, a primary reason why control arms have such an advantage over spindles, which have no effect on alignment.
Therefore, moving the upper control arm in or out (relative to the frame) is how camber is controlled. Moving the upper arm out gets you more positive and moving it in results in negative camber. If camber is out of adjustment, you will see uneven tire wear. Typically, the truck will pull to the side with the most positive camber. As a general rule, if you drive like a maniac, a little negative camber (-1/4 to –1/2 degree) may actually improve handling.
THIRD LAW OF ALIGNMENT: As alluded to above, there is no absolute right alignment. It is subject to driving conditions, and personal styles. Just make sure your truck handles safely and does not wear your expensive tires needlessly.
FOURTH LAW OF ALIGNMENT: Alignment is measured when the vehicle is still but is only important when it's in motion. We measure and setup the alignment setting when it is still, hoping for the optimal alignment when driving. Strictly speaking, your truck is technically out of alignment when it is parked. When driving, however, the suspension moves up and down, causing the camber and toe to change, while your caster setting intends to optimize your camber and toe.
THE FIFTH LAW OF ALIGNMENT: When lowering you truck with an engineered lowering kit you should ALWAYS be able to align to OEM specs. Period. With today’s technology there is no excuse for a lowering kit that can’t be aligned to factory or you’re own high performance set-up.
I’ll end this article with my speech about regular maintenance. Yeah, yeah, I know you've heard it all before, but I think it's worth repeating. If you can find a good alignment guy, it’s not a bad idea to perform regular alignment checks, especially if you have expensive, high-quality wheels and tires and especially if you notice your truck pulling to one side or if you hit a “pothole” etc. It optimizes tire wear and handling and can actually save you money over time.
For more great suspension information and articles, visit www.calmaxsuspension.com.