The 604 Differential/Case Saver positively secures the 604 pinion shaft into its carrier on both sides, preventing costly carrier and case damage. Made of quality materials and precision crafted, this cost-effective problem solver allows for the use of questionable carriers and prevents expensive comebacks. This simple solution is a must for all 604 rebuilds.

Positively secures pinion shaft and improves lubrication to the gear
Virtually eliminates case breakage from loose pinion shafts
Allows you to use previously borderline and questionable carriers
Provides a low cost alternative to replacing the transmission case