What’s the expected life span of these motors? I’m looking to run one continuously for quite a long time without brush replacement or lubrication. It’s for a store sign, so it would be spinning a fairly low load for ~10 hours per day most days a year. Would I get a few years of life out of this before it needed a rebuild?
Unfortunately, we do not have our motor or gearbox lifetimes well characterized, and in general, the lifetimes can vary depending on many different factors. If you are operating it at light loads, then the 37D gearmotors should have a lifetime on the order of a few hundred or perhaps a few thousand hours before the brushes of the motor wear away to the point that the motor no longer functions. So a few years in operation like you have described is probably expecting too much from any brushed DC motor.
For applications like this, brushless motors are typically used since there are no brushes to wear out. We do not carry any three-phase BLDCs, but we do carry stepper motors (which are two-phase brushless motors); perhaps one of those could work for you.