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Technical - Cab Assist Step Cracking (Repl Step, Install Rubber Insulators)

Subject:Cab Assist Step Cracking (Replace Step and Install Rubber Insulators)

Models:1995-2000 Chevrolet and GMC C6-7 Conventional Models
With Single Fuel Tank


This bulletin is being revised to change a part number. Please discard Corporate Bulletin Number 00-08-63-001 (Section 8-Body and Accessories).

Condition

Some owners may comment on the cab assist step cracking around the mounting bolts.

Cause

Engine vibration may cause this condition. This vibration results in flexing at the mounting bolts causing the step material to crack.

Correction

Replace the cab assist step, P/N 15559039. Install new rubber insulators, P/N 15755104, between the step and mounting supports at the bolt hole locations on affected vehicles. A total of four strips will be required, two on each support brace. These rubber insulators will aid in dampening the resonance and should prevent the step from cracking. Use the service procedure and part numbers listed below.

  1. Remove the step mounting bolts, the nuts and the washers.
  2. Remove the step from the supports.

    3. Object Number: 656258 Size: LH
  3. Position the rubber insulator strips on the top two outer side edge surfaces of each step support, 3 mm (0.12 in) in from each edge (two strips per support) (left side shown, right side similar).
  4. Install the new step to the supports. Maintain the position of the insulator strips.

    5. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Install the mounting bolts, the nuts and the washers.

    6. Tighten
    Tighten the nuts to 20-25 N·m (15-18 lb  ft).

Parts Information

Part Number

Description

Qty

15559039

Step, Cab Assist

1

15755104

Insulator, Asst Step Frt Supt

4 Strips

Parts are expected to be available 2-7-2000 from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

B1921

Step, Cab Assist - Replace

0.2 hr *

* This time is updated from the current Labor Time Guide. The next issue will contain this change.

Add 0.1 hr in other labor hours to install rubber insulators.