What Is A Lower Control Arm And Why Is It Important?
Your Nissan has two lower control arms. Also known as an A-arm, a lower control arm plays a big role in the suspension system. When one of your lower control arms fails, you’ll experience serious steering and handling issues. So it's quite important to know a thing or two about lower control arms.
To help you better understand lower control arms, here’s a comprehensive write-up on this part.
What Does A Lower Control Arm Look Like?
A typical lower control arm looks like a blocky metal "A". The inner end of the lower control arm has two bushings inside. That end connects to the vehicle's chassis. The other end of the lower control arm connects to the lowermost area of the front wheel. Here's an example of what a lower control arm looks like:
Why Does Your Nissan Need A Lower Control Arm?
All cars and trucks have lower control arms. There's always one lower control arm at each front wheel. Many trucks and SUVs have upper control arms, too.
The lower control arm is an important part of the suspension system. It provides a strong connection between the wheel and the suspension system. It keeps the wheel in sync with the rest of the suspension system. For example, what happens when one of your front wheels hits a pothole? The lower control arm helps the wheel move up and down with the suspension system.
How Does A Lower Control Arm Work?
The wider end of the control arm (the lower part of the "A") connects to the chassis. This connection acts like a hinge. The narrower part (the top part of the "A") has a ball joint on it. The ball joint connects to the steering knuckle. This enables the wheel to turn in any direction with the lower control arm connected to it.
When the wheels move up and down, the control arms keeps them stable and level with the rest of the suspension system. Here's a gif that shows the lower control arm in action:
Source: Boomer Garage
Is The Lower Control Arm The Same As The Upper Control Arm?
Yes and no. The upper control arm serves the same purpose as the lower control arm. The only difference is that the upper control arm connects to the uppermost part of the steering knuckle. It's also shaped and sized differently from the lower control arm. For that reason, these parts aren't interchangeable.
What Happens When Your Lower Control Arm Fails?
Lower control arms should last forever because they're strong, solid pieces of metal. But they can still break or wear out under certain circumstances. Here are a few scenarios where this could happen:
- A rock or another large object strikes the lower control arm and fractures the metal.
- A rock or another large object strikes the lower control arm and bends the metal. This throws the alignment out of whack.
- The ball joints wear out and cause the wheel to fall out. This breaks the lower control arm in the process.
- The vehicle gets into a bad accident, where the impact is heavy enough to break the lower control arm.
- The bushings in the control arm wear out, letting it move around more than it should.
So what happens when the control arm breaks? There's no longer anything holding the wheel in place. You won't be able to drive any farther. If it breaks while you're moving, it might cause an accident. Most often, the control arm gets damaged or the bushings wear out. When this happens, you'll notice:
- Inability to steer well
- Poor alignment
- Uneven tire wear
- Sloppy handling
- Squeaking noises or clunks when going over bumps
Replacing Your Lower Control Arm
Nissan lower control arm part no. 54500-1PA0E
Replacing the lower control arm is something you can do yourself with the right tools and expertise. It’s actually much cheaper than hiring a shop to take care of the job for you. You’ll save the most money if you order an OEM replacement lower control arm from us. It’s because we offer wholesale pricing on genuine OEM Nissan parts.
If you have a 2007-2009 Nissan Altima and you’re looking for a replacement lower control arm, part no. 551B0-JA000 is what you need. If you have another Nissan model, we have an entire catalog of OEM lower control arms for you to choose from. Look up your Nissan model to get the right lower control arm for your car.
Contact us if you have any questions or if you need help finding the right replacement lower control arm for your Nissan!