Why choose adjustable control arms over fixed control arms.

This is another great RUKSE article explaining what control arms do for Jeep, Dodge and Ford applications. We will discuss what a control arm does, why you should invest in longer aftermarket control arms, and why you should pick adjustable control arms over fixed control arms.

WHAT DO CONTROL ARMS DO?

Control arms hold the axle centered between the wheel wells when looking at them from the side of the vehicle. The keep the axle correctly aligned and prevent problems that will transfer into and hamper the steering ability of the vehicle.

WHY DO YOU NEED LONGER AFTERMARKET CONTROL ARMS?

Longer control arms are necessary for any lift size over 2 inches. They are needed to make sure the axle is centered correctly. When you lift the vehicle it pulls the axle toward the cab, the larger the lift the more it gets pulled toward the cab. Then the tires can actually hit fenders or other suspension parts causing rubbing or a restricted turn radius. They are also necessary to replace weak OE control arms that are prone to break with a large lift. OE arms are made of stamped steel that is very thin and have a large surface area exposed to the elements. This causes them to rust quickly and become brittle (see photo of a rusted control arm).

WHAT IS THE DIFFERENCE BETWEEN FIXED AND ADJUSTABLE CONTROL ARMS?

Fixed control arms help push the axle back towards center, but the problem is that unless you get the correct measurement your axle may be pushed to forward or backward. Once bought the length of the control arm is fixed and can only be used on the lift for which they were installed for. This limits your ability to make changes to the lift size of the vehicle.

The answer to make sure you get a correctly aligned axle is adjustable control arms, because they allow you to dial in your adjustment exactly where you need the axle to be set. If you decide you want to put on a bigger lift or make suspension changes adjustable control arms will allow you to make the necessary adjustments to keep the axle correctly aligned. They are also necessary to replace weak OE arms that are prone to break with a large lift. OE arms are made of stamped steel that is very thin and have a large surface area exposed to the elements. This causes them to rust quickly and become brittle (see photo of a rust control arm).

WHERE DO CONTROL ARMS MOUNT?

Most off-road vehicles and trucks have control arms in lower and upper mounting points, and work on either front and/or rear axles. Upper control arms are not as long as lower control arms because usually the mounting point is not as far away.

The following is a list of some popular Dodge, Jeep, and Ford aftermarket control arms and the mounting points on the vehicle:

1984-2001 Jeep Grand Cherokee XJ - Front Lower Control Arm mount on uni-body, Front Upper Control Arm mount on axle

1993-1998 Jeep Grand Cherokee ZJ - Front and Rear Lower Control Arms mount the same as Cherokee XJ, Front and Rear Upper Control Arms mount on axle and body mount points.

1997-2006 Jeep Wrangler TJ - Front and Rear Lower Control Arm, Front and Rear Upper Control Arm.

1999-2004 Jeep Grand Cherokee WJ Front Lower and Upper Control Arm mount to axles. Rear Lower Control Arms mount to frame.

2007-Present Jeep Wrangler JK Front Upper Control Arm mount to axles.

1994 - 2009 Dodge Ram Truck 1500 (to 2001) 2500, 3500 Lower and Upper Front Axle Only.

1997-2002 Ford Expedition Lincoln Navigator Front Lower Fixed Control Arm.

HOW SHOULD CONTROL ARMS BE ADJUSTED?

Each set of control arms should be adjusted together but it is recommended to start with the uppers. It is easier to do it with the the vehicle jacked up and the axle able to move freely. Once the lowers are adjusted then you can adjust the lowers. Please see a previous article on correct adjustable control arm adjustment lengths in our Hub Pages directory. Proper stands and or a lift should be used. It is best to have your vehicle aligned by a professional.

WHAT OTHER FEATURES SHOULD A GOOD AFTERMARKET CONTROL ARM HAVE?

With all aftermarket control arms it is recommended that you have a coating on them that protects from rust. Not all coatings are the same. Control arms should be either powder coated or ceramic coated. Ceramic coating has better rust protection and generally lasts longer. Ceramic coating actually bonds with the metal providing a new sacrificial surface that is impact resistant. Not all powder coating is the same, you can vary the thickness for a cheaper cost, you can add a primer for additional protection, and you can prep the product for better adhesion.

All of control arms you purchase should be sand blasted and heat treated to remove oils, contaminants, and blemishes before coating. They should have a primer coat, and a thick layer of powder coating. This provides a great looking control arm that lasts a long time. Polyurethane bushings are also a must, these allow for a little flex but last longer than rubber bushings. Make sure the arms have steel shims and you should have a product that lasts a long time.

Hopefully this will answer that critical question whether you should save some money and get fixed control arms or spend a little more and get adjustable control arms. If you are building a vehicle to keep for a while then the answer is adjustable control arms. Avoid making the mistake that some consumers make thinking they will never lift their vehicle higher. In our experience we have seen that most people who start never stop improving or lifting their vehicle to new heights!

Ruk Development Inc. manufactures suspension and high performance racing products. Rukse Jeep, Dodge, and Ford Adjustable Control Arms is a product we have developed.