Diagnosis And Testing - Steering Column Lower Coupling

The steering column lower coupling and its flexible joint must be inspected whenever any of the following conditions exist:

• After the vehicle has been involved in a collision which deploys the airbag, regardless of the extent of damage to the vehicle.
• After the vehicle has been involved in an undercarriage impact which results in any type of damage or bending of front suspension components or the frame of the vehicle.
• Under any conditions which result in the steering gear, steering column or steering column shaft receiving a force great enough to move the steering column or shaft forward or rearward in the vehicle.

Inspect the lower coupling shaft and its flexible joint for any of the following conditions:

• seized or binding bearings
• loose bearing stakes
• bearings not fully seated
• shaft bent
• shaft too short (see measurement procedure below)

Upon inspection, if any of the above conditions exist, replacement of the entire steering column lower coupling is necessary.

The shaft area of the lower coupling is a dual-stage type. See Fig 1. It has a Stage 1 and a Stage 2. Upon impact, Stage 1 slides into Stage 2. Measure the length of Stage 1 from Point A to Point B. See Fig 1. If the distance between Point A and Point B (length of Stage 1) is under 1.5 inches (38 mm), replace the coupling.

Fig 1: Dual-Stage Shaft Coupling

Courtesy of DAIMLERCHRYSLER CORP.