HERE'S WHAT AAA HAS TO SAY.
You don't have to believe us. But you should trust what The American Auto Association has to say. The Wiper Blade Company does and we support their cause for safe driving.
AAA - "Most people realize the importance of being able to see the road ahead clearly when driving in wet weather. That's why windshield wipers were invented. In 1916, a motorist struck a man on a bike during a rainstorm because water on his windshield blurred his view."
"AAA recommends that you replace the wiper blades every 6 to 12 months, and more in hot, sunny climates if you vehicle sits outside all day."
"For safe driving, wiper blades should be replaced at the first sign of trouble. Streaking, chattering and noisy operation are all clues that the wipers are nearing the end of their useful service life."
"Don't wait until you can barely see where you are going before thinking about changing your blades."
source AAA 2008 stock#4147