K 1500 Suburban 4WD V8-5.3L VIN Z Flex Fuel (2003)
If the drive belt(s) is the incorrect length, the drive belt tensioner may not maintain the proper tension on the drive belt(s).
Drive Belt Falls Off Diagnosis
Test Description
The number(s) below refer to the step(s) in the diagnostic table.
2. This inspection is to verify the condition of the drive belt(s). Damage may have occurred to the drive belt(s) when the drive belt(s) fell off the
pulley. Inspect the drive belt(s) for cuts, tears, sections of ribs missing, or damaged belt plys.
4. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using a straight edge in the pulley grooves across
two or three pulleys. If a misaligned pulley is found, refer to that accessory drive component for the proper removal and installation procedure of
that pulley.
5. Inspection of the accessory drive pulley(s) should include inspecting for bends, dents, or other damage that would prevent the drive belt from
seating properly in the pulley grooves or on the smooth surface of a pulley when the back side of the drive belt(s) is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belt(s) to fall off.
7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive bracket(s) moving under load. Over tightening the fasteners may cause
misalignment of the accessory component bracket(s).
Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a body component or another part of the vehicle to make rumbling noise.
The drive belt(s) may have a condition that can not be seen or felt. Sometimes replacing the drive belt(s) may be the only repair for the symptom.
