Initial Inspection and Diagnostic Overview
Accessory DriveInspection and Verification
1. Verify the customer's concern by operating the engine to duplicate the condition.
2. Inspect to determine if any of the following mechanical concerns apply.
3. Inspect for drive belt cracking/chunking/wear.
4. If the concerns remain after inspection, determine the symptoms. GO to Symptom Chart. Under severe operating conditions (high temperature, low humidity), drive belt rib cracking can occur at less than 96,000 km (60,000 miles). Drive belt rib cracking (cracks across grooves):
^ is not a reason for concern.
^ has no detrimental effect on drive belt performance. Cracks parallel to grooves are acceptable.
The drive belt is still perfectly functional until rib chunking occurs. Drive belt chunking is where the rubber material actually chunks out between the cracks. A new drive belt should be installed if chunking occurs.
V-Ribbed Belt With Cracks (Acceptable):
V-Ribbed Serpentine Drive Belt with Cracks Across Backing
V-Ribbed Belt With Chunks Of Rib Missing (Not Acceptable):
V-Ribbed Serpentine Drive Belt with Chunks of Rib Missing
5. If the concern(s) remains after inspection, determine the symptoms. GO to Symptom Chart. Symptom Related Diagnostic Procedures