February 22, 2016
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.
OE Part No. 17803689, 08663580View Instructions Find a Distributor
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. The unique Sonnax Smart-Tech housing design 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.
Smart-Tech input housing kit with heavy duty input shaft 77733-10K fits 298mm torque converter units. The high-strength shaft features many unique refinements available only from Sonnax, including a unique design that protects against failure from stress cracks. Both the housing and shaft also are available separately.
Requires '91-later 3-4 apply ring; requires '87-later ring gear; requires '97-later stamped steel forward piston; requires '97-later dual-cage return spring; requires '87-later forward backing plate. Cannot be used with aluminum forward piston or Sonnax billet forward piston 77764-01. See instructions for further detail.
February 22, 2016
March 02, 2016
July 14, 2016
June 06, 2018
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