GM Service Manual Online
For 1990-2009 cars only

Some vehicles may exhibit a condition where the windshield wipers chatter and/or wipe unevenly. Several items may contribute to this condition. To completely repair this condition, ALL of the items listed should be tested and repaired as necessary.

    â€¢ Clean the windshield glass.
    â€¢ Clean the wiper blade elements.
    â€¢ Perform the wiper arm pressure test.
    â€¢ Inspect the wiper blade element set.