A.O. Smith is the industry standard for swimming pool OEM and replacement pump motors.  They carry a standard 2 year warranty and are relatively easy to replace.  The biggest challenge is often times finding the correct replacement for your existing motor.  Years of sun, dirt, water stains and general neglect can make reading your motor label difficult.

The most important thing to match when replacing pool motors is the Service Factor Horsepower, or SFHP.  SFHP is the product of HP rating and Service Factor.  

NOTE:  Total Horsepower (Horsepower x Service Factor) of replacement motor must meet or exceed current pump motor.