THM 4L60-E ACCUMULATOR PISTON WEAR

COMPLAINT: When the accumulator piston wears with an "Egg-Shaped" hole where the accumulator piston strokes, it can create a delayed engagement to drive, slipping condition in forward gears, slipping 1-2 shift, slipping 3-4 shift, depending on which accumulator piston is worn, and how bad it is worn.

CAUSE: The cause may be, a worn accumulator piston pin bore (See Figure 1).

CORRECTION: Replace the accumulator piston with the proper part number from "Service Information" as shown below.

SERVICE INFORMATION:
1-2 Accumulator Piston (Package of 2) ...............................................................8684429
3-4 Accumulator Piston (Package of 2) ...............................................................8682096
Forward Clutch Accumulator Piston ...................................................................8679738

Service Note:
The THM 4L60-E, 3-4 accumulator piston is same as 700-R4.
The THM 4L60-E, 1-2 accumulator piston has a smaller pin diameter.
The THM 4L60-E, forward accumulator piston is a smaller outside diameter.

Get some car tools like Launch CReader for more?