Broken Garage Door Spring? A Broken Spring Is Very Common, They Work Off Of A Cycle Life. Most New Homes Have 10,000 Cycle Springs Installed On The Garage Door. A Cycle Is When The Door Opens & Closes 1 Time. We Always Try To Replace With At Least 18,000 Cycles For Longer Life. Two Springs Are Better Than One Because If The One Spring Breaks The Cables Will Come Off Leaving You With A Garage Door With A Dead Weight Of 180lbs.Plus. Two Springs Will Keep Your Cables On In Most Cases Allowing The Door To Be Lift With Only 90lbs. Of Dead Weight, This Way You’re Less Likely To Be Trapped In The Garage.