Because most Rendon garages date to the early 90s, the springs we replace out here are almost always standard torsion, wound to fit a steel track system that hasn't changed much in thirty years - parts are easier to source than the odd sizes we track down for older housing stock. The openers tend to be chain or belt drive units installed sometime after the original build, not the original hardware, so age of the door and age of the opener don't always match. Given the moderate heat load this part of Texas carries, we see more wear on rubber seals and weatherstripping than on the mechanical guts of the opener itself - sun and heat break down the bottom seal faster than they wear out a motor. If your door was installed with the house in the early 90s and has never had the springs replaced, it's worth having them checked; torsion springs are rated by cycle count, not calendar years, and thirty-plus years of daily use is well past what most are built for.