sonnax-black Facebook-color LinkedIn-color maillink printlink r_and_r_only SERVOFIX-logo-web Twitter-color VBFIX-logo-web video-logo-web warranty_only Youtube-color

WARNING!

Earlier versions of this kit required an aluminum forward piston. It is recommended to follow the specific instructions provided during assembly to avoid a mismatch of parts.

4L60, 4L60-E, 4L65-E, 4L70-E

Smart-Tech® Input Housing Kit
Part No. 77733-06K

View Instructions

Limitations of the GM 4L60-E, 4L65-E, 4L70-E 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.

Sonnax Smart-Tech input housing kit 77733-06K makes room for a taller clutch pack anchored in place by a stronger backing plate, making it the only way to increase clutch capacity and protect against destructive heat. Numerous other improvements to the housing ensure maximum durability and protection against failure in higher horsepower, higher pressure applications. The housing also is available with a pre-installed, heavy-duty input shaft.

  • 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
  • Treated housing is 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

Learn more about the Sonnax Smart-Tech Input Housing

The Smart-Tech input housing kit is the best in the business. Have it in my 4L65E putting down over 700rwhp. Zero issues, no slippage and low temps. Sonnax parts are #1 in my book.

N. Rodriguez
Koncept Motorwurks
Covina, CA

Requires '91-later 3-4 apply ring; Requires '97-later ring gear; Requires '97-later stamped steel forward piston. Cannot be used with aluminum forward piston or Sonnax billet forward piston 77764-01. See instructions for further detail.

  • PTFE Impregnated Rear Stator Support Bushing
  • Modified Input Housing
  • Input Drum Reinforcement Sleeve
  • Overrun Piston Inner Seal
  • 3-4 Clutch Apply Plate
  • 3-4 Clutch Return Springs (10)
  • Bolt-on Anchor Plate
  • Overrun Piston Outer Seal
  • Socket Head Cap Screws (15)
  • Overrun Piston

February 22, 2016

Too Close For Comfort: Pinpointing 4L60-E Gear Train Assembly Problems

Steve Garrett

Topics: Transmission GM 4L70-E Transmission 4L60-E Transmission 4L65-E Transmission

Read Now

March 02, 2016

Building the Killer 4L60-E

Topics: Diagnostics And Theory Rebuilding Tips Transmission GM 4L70-E Transmission 4L60 Transmission 4L60-E Transmission 4L65-E Transmission

Read Now

October 16, 2012

Transmission Report: New Sonnax Improvements for the 4L60 3-4 Clutch

Topics: Transmission Report Newsletters Rebuilding Tips Valve Body Reaming Transmission GM 4L70-E Transmission 4L60 Transmission 4L60-E Transmission 4L65-E Transmission

Read Now

July 14, 2016

Transmission Report: "See" More, Spend Less with Vacuum Testing

Topics: Transmission Report Newsletters Transmission

Read Now

February 22, 2016

Eliminate 3-4 Clutch Failure with the Smart-Tech® Input Housing

Topics: Diagnostics And Theory Transmission GM 4L70-E Transmission 4L60 Transmission 4L60-E Transmission 4L65-E Transmission

Watch Now

  • 77733 06k combo
  • 77733 06k
  • Smart tech web image
  •