PATC Sells Transmission Sun Shells, Sonnax Smart Shell, Beast Shell. We have heavy duty TCS sun gear shells and more.

In GM 4L60, 4L60-E, 4L65-E and 4L70-E units, bulky aftermarket shells always fall short when splines continue to strip and the shells break under stress. A chronic problem with both OE and thicker aftermarket shells is failure of the rear planetary bearing. From daily jobs to extreme builds, the Sonnax SmartShell heavy-duty reaction shell kit 77749-02K is the only way to prevent shell failure AND protect the bearing.

The SmartShell avoids the weight found in traditional, heavy-duty aftermarket shells thanks to a unique combination of improved design and manufacturing for a super strength shell that’s only slightly bulkier than OE. To prevent thrust loads from overwhelming the captured planetary bearing, the SmartShell features a larger bearing and custom roller clutch race. These parts re-route thrust loads through the carrier, completely bypassing the delicate bearing.

• Stops spline stripping
• Prevents hub breakage
• Eliminates planetary bearing failure

Bulky aftermarket shells always fall short when splines continue to strip and the shells break under stress. A chronic problem with both OE and thicker aftermarket shells is failure of the rear planetary bearing. From your daily jobs to extreme builds, the patented SmartShell is the only way to prevent shell failure AND protect the bearing.

This Sonnax video takes you inside the sun gear shell to see the source of common failures and learn how only the SmartShell can stop them all.