Air Core stepper motors were commonly used in GM clusters from 1995-2002. They were used in prior years, however it was a different style than the ones we are offering and less in demand by customers.

There is actually oil inside of these steppers that cushion the movement of the needle. This oil creates a smooth needle movement.  When the oil leaks out then the needles will wildly bounce around.

Later models obviously went away from this and used small gears and magnets instead to save on costs.