Replacing the Lateral Arm on Your 1978-1986 Chevrolet Impala
Address rear-end clunks and wandering by understanding the function and replacement of your Impala's lateral arm.
- A worn lateral arm on your Impala will cause clunking noises and a feeling of instability from the rear of the car.
- For this model year, a new aftermarket arm from a brand like Dorman is the standard, cost-effective repair solution.
- Failure of this part is due to the natural aging of rubber bushings, not a specific vehicle defect.
- Replacement is a straightforward DIY job for those with basic tools.
Understanding the Lateral Arm on a Classic Impala
On the 1978-1986 Chevrolet Impala, the rear suspension uses a solid axle with coil springs. A key component of this design is the lateral arm, often called a panhard bar. 🎬 Watch this guide to understand how panhard bars function. It's a simple but vital link that keeps the entire rear axle located correctly from left to right. Over decades of driving, the original rubber bushings at each end of the arm can dry out, crack, and fail. This allows for unwanted movement, which leads to the common symptoms of a worn-out lateral arm.
Symptoms of a Failing Lateral Arm
When the lateral arm bushings wear out, the rear axle can shift slightly from side to side. This can cause a number of noticeable problems while driving. If you experience these issues, it's a good idea to inspect your lateral arm and its bushings.
🎬 Learn more about identifying the symptoms of bad control arms.- Clunking or Thudding Noises: You may hear clunking sounds from the rear of the car, especially when going over bumps or making turns. This is the sound of the loose arm moving and hitting its mounting points.
- Loose or Wandering Steering: A feeling that the rear of the car is “steering itself” or wandering on the road is a classic sign. This happens because the axle is no longer held firmly in place, affecting stability.
- Uneven Rear Tire Wear: While less common than other symptoms, excessive side-to-side movement can contribute to abnormal tire wear over time.
Choosing the Right Aftermarket Lateral Arm
For a vehicle from this era, finding a new Original Equipment Manufacturer (OEM) part from GM is highly unlikely. The market primarily consists of aftermarket replacements.
Dorman: An OE-Style Replacement
Dorman is a widely available aftermarket brand that produces replacement parts designed to fit and function like the original. For a standard repair on a daily driver or a simple restoration, a Dorman lateral arm is a reliable and cost-effective choice. These arms are typically made from stamped steel and come with new rubber bushings already installed, making replacement straightforward. Forum discussions among car enthusiasts often consider Dorman a suitable option for standard, non-performance applications.
Replacement Cost Comparison
| Part Type | Price Range | Notes |
|---|---|---|
| New Aftermarket (Dorman) | $59.63 | The most common and cost-effective option. Comes with new bushings. |
| New OEM | N/A | New OEM parts for this vehicle are generally no longer available. |
| Used OEM | $25 - $75 | Can be found at salvage yards, but bushings will likely be old and require replacement. |
Known Issues, Recalls, and TSBs
Searches of the National Highway Traffic Safety Administration (NHTSA) database and other sources did not reveal any specific recalls or Technical Service Bulletins (TSBs) for the lateral arm on the 1978-1986 Chevrolet Impala. Problems with this part are almost always due to age-related wear and tear of the rubber bushings, rather than a manufacturing defect.
Frequently Asked Questions (FAQ)
Is a lateral arm the same as a panhard bar?
Yes, for this vehicle, the terms are used interchangeably. They both refer to the bar that controls the side-to-side movement of the rear axle.
Can I just replace the bushings instead of the whole arm?
Yes, replacement bushings are available. However, pressing out the old bushings and installing new ones requires special tools. 🎬 See how to install new performance bushings in your arms. For many DIY mechanics, replacing the entire arm, which comes with new bushings pre-installed, is faster and easier.
Do I need an alignment after replacing the lateral arm?
Replacing the lateral arm does not typically affect wheel alignment angles like camber or toe. However, if you are replacing other suspension components at the same time, an alignment is recommended.
How difficult is it to replace the lateral arm?
This is a relatively simple job for someone with basic mechanical skills and tools. It involves removing two bolts, swapping the arm, and reinstalling the bolts. The most difficult part can be dealing with rust on the original bolts.
Helpful Videos
![Panhard Bars 101: The ULTIMATE [MUST-WATCH] Info and Installation Guide!](https://img.youtube.com/vi/FiRk3Q5VhmM/mqdefault.jpg)
Technical Specifications
This part is also commonly referred to as a Panhard Bar or Track Bar. It is a single steel arm with rubber bushings at each end, mounted horizontally between the frame and the rear axle.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.