For maximum effectiveness and longest element life, the windshield and wiper blades should be kept clean. Dirt, tree sap, road tar and so on will cause streaking, smearing and blade deterioration if left on the glass. It is advisable to wash the windshield carefully with a commercial glass cleaner at least once a month. Wipe off the rubber blades with the wet rag afterwards. Do not attempt to move the wipers back and forth by hand; damage to the motor and drive mechanism will result.
If the blades are found to be cracked, broken or torn, they should be replaced immediately. Replacement intervals will vary with usage, although ozone deterioration usually limits blade life to about one year. If the wiper pattern is smeared or streaked, or if the blade chatters across the glass, the blades should be replaced. It is easiest and most sensible to replace them in pairs.
WIPER REFILL REPLACEMENT
See Figures 1, 2 and 3
Normally, if the wipers are not cleaning the windshield properly, only the refill has to be replaced. The blade and arm usually require replacement only in the event of damage. It is not necessary (except on new Tridon refills) to remove the arm or the blade to replace the refill, though you may have to position the arm higher on the glass. You can do this by turning the ignition switch on and operating the wipers; when they are positioned where they are accessible, turn the switch off.
There are three basic types of refills and your Cadillac could have any kind, since aftermarket blades and arms may not use exactly the same type refill as the original equipment.
Some types, such as Anco use a release button that is pushed down to allow the refill to slide out of the yoke jaws. The new refill slides in and locks in place. Some of these refills are removed by locating where the metal backing strip or the refill is wider. Insert a small screwdriver blade between the frame and metal backing strip. Press down to release the refill from the retaining tab.
Another type, such as Trico, is unlocked at one end by squeezing two metal tabs, and then sliding the refill out of the frame jaws. When the new refill is installed, the tabs will click into place, locking the refill.
The third, or polycarbonate type is held in place by a locking lever that is pushed downward out of the groove in the arm, to free the refill. When the new refill is installed, it will lock in place automatically.
Regardless of the type of refill used, make sure that all of the frame jaws are engaged as the refill is pushed into place and locked. The metal blade holder and frame will scratch the glass if allowed to touch it.