ACDelco Automatic Transmission Reaction Sun Gear Shell

The ACDelco Automatic Transmission Reaction Sun Gear Shell (also called a reaction sun gear shell or planetary sun gear drum) is a replacement internal component for automatic transmissions. It is part of the planetary gear train. It helps transfer and direct power through the transmission so the unit shifts and drives correctly.

Key Features:

• Replacement part for the reaction sun gear shell in the planetary gear assembly
• Helps keep the planetary gear set aligned and supported during operation
• Intended for transmission rebuilds and repairs where the original shell is worn, damaged, or cracked
• Backed by ACDelco, a brand with a long history of supplying GM and aftermarket parts

Replacing a worn sun gear shell during a rebuild can help restore smooth shifting and reliable transmission performance. Each part number in this product line is made for a specific transmission application. Select the correct variant for your transmission.