Why do I need to replace the OE UCA with KSP UCA after lifting?

Yuvien Royer - Writer; Automobile Expertise |

When do we need to replace the UCA(upper control arms)?

The UCA, which is found in the double wishbone structure, connects the vehicle body to the knuckle. It is responsible for better control of the vehicle during the ride and bumps.

Double wishbone suspensions are used in various models, and the UCA is an important part of this type of suspension. Although the UCA is not a load-bearing component, it is also prone to problems due to the intensity of its work.

Therefore it needs routine inspection and maintenance.

The technicians will routinely inspect your UCA and ball joints during vehicle maintenance. So please pay much attention when you notice a problem with your upper control arms.

In this article, we will explain the necessity of replacing the control arm in different situations for off-road vehicles.

2. Replace the OE control arms

If you are an off-road enthusiast, you must have gotten a lot of advice about replacing your OE control arms.

Design of the OE control arm:

Considering the durability of the OE control arms, it has a limited adjustable angle due to the conservative design of the OE vehicle components.

KSP's control arm could replace the OE control arm and get a larger swing angle.

upper control arms

Material of the OE control arm:

In addition to the reason for the design, materials are also an important factor. There are many OE arms made from metal sheets. It is beneficial for OE manufacturers to produce control arms with this processing technique because they can produce them in large quantities quickly and inexpensively. The OE control arm can handle most road surfaces, but it is common to deform or break during high-intensity off-road driving.

KSP control arm is specially designed for different models with high-intensity off-road driving. It has better strength and durability than the OE control arm. BTW, it has a stronger impact and deformation resistance.

So we have upgraded our materials in many ways to provide our customers with a better driving experience.

advantages of KSP upper control arms

In addition to what can be seen on the outside, there are many unseen upgrades.

For example, KSP's ball joints are tested for accuracy and pressure before leaving the factory to ensure the durability of ball joints. So that the mechanical performance of the ball joints are better than the OE’s.


At this time, with the modified shock rod and shock spring, the swing arm can play a better shock effect. So the shock travel of the vehicle will be greatly increased.

Matching the suspension modifications

When you try to search for the Lifting impact on vehicles, it doesn't take long to find the keywords ''upper control arm" and "ball joints".

1.KSP UCA can adapt to the change of angle after lifting

If you have lifted 2 inches and more, then you will have to replace your OE UCA.

So please keep in mind that the OE UCA will definitely affect the wheel travel/throw, suspension durability and wheel alignment before lifting your vehicle. And such effects will be magnified as the lift height increases.

We should find this truth in our daily life: The most easily damaged part of the item in the process of use is the joints. 

The same is true for the upper control arms, which is an important part of the double wishbone suspension.

The OE control arms and ball joints designed for the stock body height can work well with the softness and stiffness of the shock.

The angle between the UCA and the knuckle decreases as the vehicle is lifted. It is easy to see that the swing space of the ball joints is compressed at this time.

The ball seat of the control arm can almost touch the knuckle, which may lead to wear of the ball joints, breakage and the oil leakage of the dust cover, or even the detachment of the ball joints.

The adjustment range of the stock ball joints is not adequate for the suspension system at this time when the balance of the vehicle is upset by the addition of the lift kits.

At this point, the replacement of the control arm is not an option, but a requirement.

At this time, it is no exaggeration to say that the state of the suspension will threaten not only the structure of your vehicle, but also your safety!

We often receive such questions from our customers: Why is the size of your control arms the same as the OE one?

But in fact, we have completely upgraded the body of the control arm, the bushing, and the ball joints. Different adjustments were made according to the specific lifting height of each model. But the certain changes are not obvious without professional comparison.

Taking the body of control arm as an example, we have modified its curvature to allow it to work better in the suspension.

The material of the bushing has also been fully upgraded, the durability is better than the OE one.

The angle of the ball joints is then adjusted as shown in the picture above. This allows for a more reasonable range of motion, thus improving its safety.

That' s why replacing the control arms is a project you can' t get around if you want to improve both vehicle height and off-road performance.

2.Match the aftermarket shocks

The performance of OE UCA is unable to meet the needs of the shock modification.

If you choose to modify the Suspension Lift Kits.

By the way, the bright color of the aftermarket parts can be disharmonious with the color of the OE control arm.

It would be a waste to stuff a shock into the stock suspension to get more travel in the shock.

The stock control arm will not be able to give more travel to the upgraded shock assembly due to its conservative design, which will lose the expected effect and meaning of the modification.

So you will see the shock assembly will be sold together with the control arm.

As we have stressed many times, the modification of a vehicle is not a stand-alone action.

It’s not something that can be done by modifying the wheels or the shocks separately.

A single modification of shock system won’t meet your needs if you want to improve the overall handling of your vehicle.

So it’s necessary to seek the advice of professionals when it comes to specifics, and please do not go overboard with the pursuit of extremes.


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