Description
4L60 / 4L60E Smart-Tech® Input Housing Kit with Heavy Duty Input Shaft, Sonnax 77733-10KB.
For ’85-later units with 298mm converter, 30-spline input shaft. For ’82–’84 units with 27-spline input shaft, converter and stator shaft will need to be updated to ’85-later design.
Limitations of the GM 4L60 series OE input housing are the root cause of 3-4 burnup in performance applications. The weak OE backing plate flexes during clutch apply, allowing heat to build up unevenly within the clutch pack’s limited space. Stop the flex and you stop 3-4 clutch failure.
Smart-Tech input housing kit with heavy duty input shaft 77733-10KB fits 298mm torque converter units. It features a revised turbine end spline without an undercut where OE shafts commonly break. Both the housing and shaft also are available separately.
- Physically larger clutch pack area for increased 3-4 clutch capacity without sacrificing clutch durability. Use your choice of:
- Eight .067″ frictions with seven .095″ steels
- Nine .062″ frictions with eight .077″ steels
- Anchored backing plate keeps clutches parallel to stop the flexing and distortion that leads to heat build-up
- 100% New housing optimizes input shaft fitment and is further upgraded for significantly more resistant to fatigue failure
- Steel reinforcement sleeve prevents breakage in the spline area
- Custom backing plate replaces OE retaining ring to eliminate risk of blowout
- High-strength 300M shaft
- Smart-Tech® Input Housing with Heavy Duty Input Shaft
- Bolt-on Anchor Plate
- 3-4 Clutch Apply Plate
- 3-4 Clutch Return Springs (10)
- Input Drum Reinforcement Sleeve installed
- Overrun Piston
- Overrun Piston Inner Seal
- Overrun Piston Outer Seal
- PTFE Impregnated Rear Stator Support Bushing
- Socket Head Cap Screws (15)
