OE end plugs are designed to prevent critical pressure loss by capping the bore, while also functioning as a spring or valve stop. Repetitive spring motion, valve impact and fluid pressure variations cause wear between the end plug and bore mating surface, allowing vital fluid to escape the circuit.
Wear at various OE end plugs in GM 8L45 and 8L90 transmissions allows critical leakage at the following circuits, default override, lube flow regulation, and converter lockup/release. These pressure losses impair control of clutches, effect lube flow regulation and critical converter control.
Put an end to leaks, restore hydraulic integrity and renew shift operation by installing Sonnax O-ringed end plug kit 154740-17K.
End plug deterioration or bore wear is visually detected in any of the (3) locations.