GM Service Manual Online
For 1990-2009 cars only

Keep the safety belts and the built-in child restraint harness clean and dry.

Caution: Do not bleach or dye safety belts or the built-in child restraint harness. If you do, they may be severely weakened. In a crash, they might not be able to provide adequate protection. Clean the safety belts and the child restraint harness only with mild soap and lukewarm water.