2020 BMW 840i xDrive Trailing Arm Replacement Cost

Trailing arms are a component which is not found on all vehicles. They may be found on passenger cars, SUV's, trucks, and vans, and they can be adapted to straight axle vehicles or vehicles with independent suspension. The purpose of the trailing arm is to prevent forward or rearward movement of the axle or control arm that they support, which results in increased handling characteristics, high speed stability, and better steering response. Whether on the rear or front of the vehicle, the trailing arm provides the axle or control arm with an additional mounting point to the frame. When a suspension concern arises, the trailing arm will likely be inspected along with other components to rule out or diagnose trailing arm failure.

Many control arms and drive axles have limited support from longitudinal movement, that is allowing the wheel to move forward and backwards in the wheel well, so trailing arms have been introduced to help solve that issue. The trailing arm is mounted in front of or behind the axle or control arm, and attaches directly to the frame. Both ends of the trailing arm allow the suspension to move up and down, but since the trailing arm is mounted perpendicular to the control arm or axle, the wheel and hub assembly is unable to move in any other direction. This allows for a high degree of stability, ensures necessary movement of the suspension system, and prevents the vehicle from wandering within the lane.

Trailing arm symptoms are similar to other suspension system failures, but are more limited in the effects they may have on a vehicle. Noises like squeaking, creaking, rattling or clunking may be heard when a bushing is worn. The vehicle may seem to shift to one side during acceleration or braking. The vehicle may wander around the lane while driving straight down the road, and, finally, the tires may experience swirling on the edges.