Repeated reciprocation of the 4th accumulator pistons in GM 4L80-E and 4L85-E units causes wear at the piston/pin interface. After this wear reaches a critical point, the piston bore wear allows the piston to get cocked and gall the accumulator bore. Once this bore becomes severely galled, the accumulator body must be replaced. The Sonnax 4th accumulator repair kit 34805-01K salvages accumulator housings with a worn or scored 4th accumulator bore.

Kit salvages accumulator housings with a worn or scored 4th accumulator bore
A press-in sleeve is included for easy installation
Pinless accumulator piston uses a PTFE seal to support the piston in the bore
Repeated reciprocation of the 4th accumulator pistons in GM 4L80-E and 4L85-E units causes wear at the piston/pin interface. After this wear reaches a critical point, the piston bore wear allows the piston to get cocked and gall the accumulator bore. Once this bore becomes severely galled, the accumulator body must be replaced. The Sonnax 4th accumulator repair kit 34805-01K salvages accumulator housings with a worn or scored 4th accumulator bore.

Kit salvages accumulator housings with a worn or scored 4th accumulator bore
A press-in sleeve is included for easy installation
Pinless accumulator piston uses a PTFE seal to support the piston in the bore