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Modified Item: No

Country/Region of Manufacture: United States

Custom Bundle: No

Manufacturer Part Number: 77749-02K

Brand: Sonnax

Fitment Type: Performance/Custom

Non-Domestic Product: No

Drive Type: 4WD,AWD,RWD

Manufacturer Warranty: Unspecified Length

SmartShell® Heavy Duty Reaction Shell Kit
TH700R4 4L60E 4L65E 4L70E GM TRANSMISSION
fits all varieties of these transmissions 1982-UP

Solves Multiple Problems in All Performance Applications

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