SONNAX SMARTSHELL (4L60 TO 4L70E)
# 37917K

Drive Shell (Sonnax Smart Shell)

SONNAX SMARTSHELL (4L60 TO 4L70E)

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, this Sonnax SmartShell heavy-duty reaction shell kit 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

Contents:

  • Heavy Duty Reaction Shell
  • Enclosed Thrust Bearing
  • Custom Roller Clutch Race

SONNAX Installation Instructions


Sonnax SmartShell® Heavy Duty Reaction Shell Kit - 77749-02K


Sonnax 4L60E Level 3 Transmission Build

Type of Product: Hard Parts
Qty Needed:
Years:
Alternative #: