Drop Ride Height, When To Panhard?

A Panhard bar, also known as a Panhard rod, track bar, or track rod, is a suspension link that provides lateral location of the axle. It is a simple rod bolted to the rear axle and the frame of a vehicle, found only on live axle (or solid axle) set-ups. The Panhard bar stabilises the rear axle of a vehicle, allowing the rear wheels to move up and down but not laterally (left to right). This keeps the body of the car centred over the axle and reduces rear steer.

The Panhard bar gets its name from the Panhard automobile company of France, which was founded by Rene Panhard and Emile Levassor in 1887.

Panhard bars are only needed for live axle (or solid axle) setups

Panhard bars, also known as Panhard rods, track bars, or track rods, are only required for live axle (or solid axle) setups. They are not necessary for independent rear suspension systems.

A Panhard bar is a stabilising unit designed to reduce a vehicle's side-to-side roll. It is composed of a simple rod that is bolted to the rear axle and the frame of a vehicle. The bar connects diagonally from the axle to the frame, allowing some up-and-down pitch of the rear axle in relation to the wheels. This geometry is important as it enables the vehicle to navigate uneven surfaces.

Panhard bars are typically used with coil spring suspensions. They are designed to prevent lateral movement, allowing the wheels to move vertically while restricting forward, backward, and side-to-side motion. The bar attaches to the axle and chassis with pivots that enable upward and downward swivelling, limiting the axle's movement to the vertical plane.

Panhard bars are beneficial for vehicles with live-axle suspensions that cannot accommodate a Watt's linkage due to design or practical constraints. They are also commonly used in older vehicles with solid rear axles to improve handling.

For vehicles with a solid front axle, a Panhard bar can be used to locate the front axle in a link suspension system. Upgrading to an adjustable Panhard bar can improve strength, flexibility, and adjustability, enhancing the vehicle's driveability and handling.

They're not necessary for leaf spring suspension

Panhard bars are not necessary for leaf spring suspension. The axle is directly bolted to leaf springs that have four anchor points, so the axle cannot shift much. The addition of a Panhard bar will not make a significant difference in the stability of the rear end.

Leaf springs are stiff laterally, and the installation is also pretty stiff. The only exception to this is if you have very long shackles, but even in this case, getting rid of the long shackles would be a better solution than adding a Panhard bar.

Panhard bars are easy to make, but they are not necessary for leaf spring suspension. They can be useful for keeping the rear axle centred, but this is not a common issue in leaf spring suspension setups.

Panhard bars can also cause binding as the axle flexes and articulates. This binding occurs due to the difference in movement between the leaf spring and the Panhard bar. The Panhard bar moves in an arc as the axle moves up and down, which can cause side-to-side movement in the suspension. This movement can be minimised with Del-A-Lum or similar bushings, but it is still present.

For normal driving, a Panhard bar does not offer any advantage. It is not necessary for leaf spring suspension and can even cause issues with binding and increased wear on spring bushings.

They're not essential for normal driving

Pan hard bars are often associated with lowered cars and aggressive suspension setups, but they are not a necessity for everyday driving, even with a lowered vehicle. A pan hard bar is essentially a horizontal bar that connects the axle to the chassis, and it is used to locate and stabilize the rear axle laterally. Its primary purpose is to control the side-to-side movement of the axle and maintain proper wheel alignment.

While a pan hard bar can provide benefits in certain scenarios, it is not a requirement for normal driving conditions. Here's why: For daily driving, your car's suspension is designed to provide a comfortable ride and adequate handling without the need for specialized components like a pan hard bar. Modern suspension systems are engineered to handle a range of road conditions and driving styles, maintaining stability and control.

The necessity for a pan hard bar becomes more relevant when you significantly lower your vehicle or engage in performance driving. Lowering your car changes the geometry of the suspension, and a pan hard bar can help correct issues that may arise, such as uneven tire wear or unwanted axle movement. However, for regular driving, most factory suspensions or mild lowering setups do not require the addition of a pan hard bar.

Additionally, modern vehicles often have sophisticated suspension designs that incorporate multiple locating links and control arms, which effectively control the axle movement without the need for a pan hard bar. These designs provide sufficient lateral location and stability, ensuring that the wheel alignment remains consistent during regular driving conditions. So, unless you plan on aggressive lowering or track-focused driving, the average driver won't need to concern themselves with adding a pan hard bar to their vehicle.

They're typically used with coil spring suspensions

Panhard bars are suspension links that provide lateral location of the axle. They are designed to prevent lateral movement of the wheels, allowing them to move vertically with respect to the body of the car. The Panhard rod is a rigid bar that runs sideways in the same plane as the axle, connecting one end of the axle to the car body or chassis on the opposite side. The pivots at either end of the bar allow it to swivel upwards and downwards only, limiting the axle's movement to the vertical plane.

Panhard rods are typically used with coil spring suspensions. With leaf spring suspensions, the springs themselves usually provide enough lateral rigidity. However, there are some exceptions, such as the Ford Explorer and light trucks, which use a similar rear axle damper with leaf spring suspensions.

The Panhard rod offers the advantage of simplicity. However, its major disadvantage is that the body of the car must necessarily move in an arc relative to the axle, with the radius equal to the length of the Panhard rod. If the rod is too short, it allows excessive sideways movement between the axle and the body at the ends of the spring travel. Therefore, the Panhard rod is generally less desirable for smaller cars.

When lowering a car, the Panhard bar swings in an arc, pushing the rear axle to one side. To compensate for this, the bar needs to be adjusted to a shorter length to re-center the axle. An adjustable Panhard bar is recommended for any change in ride height to improve handling and stability.

They're not always necessary for racing

A Panhard bar, also known as a Panhard rod, track rod, or track bar, is a stabilising unit designed to reduce the side-to-side roll of a vehicle. It connects diagonally from the axle to the frame of the vehicle, allowing the rear wheels to move up and down, but not laterally (left to right). This keeps the body of the car centred over the axle and reduces "rear steer".

However, a Panhard bar is not always necessary for racing. While it can improve handling and stability, it is not essential for a vehicle to function. Some racers choose to install a Panhard bar to improve performance and feel more in control of the car, while others find that they can race just fine without one.

The need for a Panhard bar also depends on the type of racing. For example, drag racers who have switched to a solid rear axle may benefit from a Panhard rod. On the other hand, vehicles with independent rear suspension systems do not need a Panhard bar.

Additionally, the decision to install a Panhard bar may depend on the desired ride height of the vehicle. If you are lowering or lifting your vehicle, an adjustable Panhard bar can help to re-centre the rear axle and maintain proper suspension geometry.

In summary, while a Panhard bar can enhance the performance of a race car, it is not always necessary. The decision to install one depends on various factors, including the type of racing, the suspension system, and the desired ride height of the vehicle.

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