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

Clean the windshield with windshield cleaner, GM PN 1050011 or equivalent. The cleaner used should be one which will not harm the paint finish or scratch the glass. The glass is clean when water no longer beads, but sheets across the entire glass surface.

Lift each blade assembly off the windshield and clean the element with a cloth saturated in full-strength washer solvent. Rinse the blade assemblies with water.

1. Run the wiper arm and the blade assemblies to the midwipe position.
2. Remove the wiper blade assemblies from the wiper arm assemblies.
3. Attach a scale to the wiper arm assembly where the wiper blade assembly attaches, and measure the force required to lift the wiper arm assembly perpendicular to the windshield to normal working height (height with the wiper blade assembly attached).
4. If the force required is not within the specifications given below, the wiper arm assembly should be replaced.

Driver side tip pressure -- 7.5-9.5 Newtons (27-34 oz)

Passenger side tip pressure -- 7.5-9.5 Newtons (27-34 oz)

Remove the wiper blade assemblies from the wiper arm assemblies. Look down the length of the wiper blade element. The rubber part of the wiper blade element that contacts the glass must be on the center line of the wiper blade assembly +/-15 degrees. Replace the wiper blade element if necessary. Refer to Wiper Blade Element Replacement .