What Causes a Clunk When Shifting in a Charger or Challenger?

A clunking sound when shifting gears or getting on and off the throttle is a common concern in rear-wheel-drive vehicles like the Dodge Charger and Challenger. While the sound can vary, it is often related to movement within the drivetrain system.

Understanding where this noise comes from begins with how the drivetrain transfers power and how its components are supported.

How the Drivetrain Transfers Power

In rear-wheel-drive vehicles, power flows from the engine through the transmission and into the driveshaft. The driveshaft then transfers that power to the rear differential, which delivers it to the wheels.

Each of these components is connected through mounting points and support systems designed to maintain alignment while allowing controlled movement.

Why a Clunk Can Occur

A clunk typically happens when there is a sudden change in load, such as shifting gears or applying and releasing the throttle. During these transitions, drivetrain components adjust to the change in force.

If there is additional movement within the system, that transition can produce a noticeable clunk or knock.

Common Areas Where Movement Can Occur

Driveshaft Center Support

The driveshaft is supported along its length by a center support bearing and carrier. This component helps maintain alignment as the driveshaft rotates.

Over time, the carrier bushing can wear or soften, which may allow additional movement during load changes.

Differential Mounting Points

The rear differential is mounted using bushings and brackets designed to balance structural support with vibration control. Movement in the differential mounting structure can contribute to drivetrain noise.

Drivetrain Connections

Connections between drivetrain components, such as joints and mounting interfaces can also allow slight movement, especially as components age.

Why the Noise Is More Noticeable During Shifting

When shifting gears or transitioning on and off the throttle, the direction and magnitude of force through the drivetrain change quickly. This can cause components to shift slightly within their normal range of movement.

If that movement increases over time, it may become more noticeable as a clunk.

Factory Design Considerations

From the factory, many drivetrain components use softer materials in key areas to help reduce noise, vibration, and harshness (NVH). While this improves comfort, it also allows for controlled movement within the system.

Over time, wear and repeated load cycles can increase that movement.

When to Inspect Drivetrain Components

If clunking becomes more noticeable or frequent, it may be a sign that one or more components should be inspected.

This can include:

Driveshaft center support and carrier bushing

Differential mounting points

Surrounding drivetrain connections

A visual inspection can often reveal signs of wear, cracking, or increased movement.

Addressing Drivetrain Movement

In situations where drivetrain movement becomes more noticeable, different approaches may be considered depending on the condition of the components.

This can include inspecting and maintaining factory components, as well as using additional support systems designed to reinforce key areas of the drivetrain.

For example, support components may be used to help maintain alignment of the driveshaft or provide additional reinforcement to the differential mounting structure.

Because the drivetrain functions as a connected system, addressing movement in one area may influence how forces are distributed throughout the rest of the system.

Summary

A clunk when shifting in a Charger or Challenger is often related to movement within the drivetrain during changes in load. Components such as the driveshaft center support, differential mounts, and connecting hardware all play a role in how forces are managed.

As these components wear over time, additional movement can occur, which may lead to noticeable noise during shifting or throttle transitions.