Aluminium Case Powerglide

The servo return spring is the source of many "mystery" band failures caused by inconsistent servo release and weak springs prone to collapse. 31668 servo piston return spring for GM Powerglide units is a lighter-than-stock spring ideal for low line pressure applications of 175 psi or less.

Note:
If this spring is installed in applications with more than 175 psi, the servo may not fully release due to the pin bias effect, resulting in dragging and burning of the band. It is recommended for higher pressure applications.