Suspension - Thumping Or Clunking Noise From Rear: Overview
Bulletin 85-3-23Date June '85
Ref. No. 85-256-3
SUBJECT: REAR SUSPENSION NOISE
MODELS AFFECTED: 1985 ELECTRAS
Some 1985 Electras may experience a "thumping", "clunking" or "loose lumber" noise from the trunk or rear suspension areas when driving over small bumps (i.e. washboard road surfaces, rough/broken pavement, etc.). This noise may be more noticeable in colder ambient temperatures (less than 32~ F).
If this condition is encountered, first inspect the rear suspension components and fasteners for proper installation and torque specifications. Check for Electronic Level Control (ELC) system for proper operation. If all suspension components are properly installed and the ELC system is working properly, the following steps should be taken: