The Sonnax Smart-Tech input housing kit 77733-06K addresses five weak areas of the GM 4L60, 4L60-E, 4L65-E, 4L70-E input housing: (1) flexing/bowing of the 3-4 backing plate, (2) limited 3-4 clutch torque capacity, (3) 3-4 snap-ring blow-out, (4) input housing breakage near the input shaft spline, and (5) input housing fatigue failure.
Flexing/bowing of OE and other aftermarket backing plates is eliminated with Sonnax’s heavy duty bolt-on anchoring plate. This unique design ensures even clamping of the 3-4 clutches in higher horsepower, higher pressure applications. By eliminating the 3-4 snap ring and using a thinner yet stiffer apply plate, space is made available for additional frictions and steels. This makes it possible to simultaneously increase clutch torque capacity and eliminate the possibility of retaining ring blow-out. A steel reinforcement sleeve prevents breakage in the spline area. Housing fatigue failure resistance and housing life are significantly improved with a special treatment process that greatly reduces stress crack formation.
Patent No. Pending
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