GM Service Manual Online
For 1990-2009 cars only

Condition

Causes

A groaning or growling noise is present in the steering pump.

    â€¢ Grounded power steering lines
    â€¢ A scored pressure plate
    â€¢ A scored thrust plate
    â€¢ A scored rotor
    â€¢ A worn cam ring
    â€¢ A low pressure relief reservoir cap
    â€¢ Restricted fluid lines (high back pressure)
    â€¢ Air ingestion in the return line
    â€¢ A damaged flow control valve
    â€¢ A low fluid level
    â€¢ Loose pump mounting bolts