Accumulator Piston Kit for 4L60E 4L65E 4L70E Transmission Pinless 1-2 3-4 Get Smooth Shifts, Fix Slippage, GM Auto Transmission Rebuild Part, Replacement for 77987-01K 7798-03K, 2-Piece
✔️ 2-Piece pinless design prevents bore leaks and piston cocking
This pinless accumulator piston kit rebuilds the internal hydraulic path in GM 4L60-E, 4L65-E, and 4L70-E transmissions. It's designed to restore smooth shifts and prevent slip by sealing the accumulator bore and stopping piston cocking caused by wear on the pin bore.
✅ Replaces part numbers 77987-01K and 7798-03K (2PC) for GM 4L60/65/70-E units
✅ Works in 200-4R applications at the 3-4 accumulator location
✅ Pinless design prevents pin bore leakage and piston cocking
✅ Dual seals stabilize and seal the bore after thousands of cycles
✅ Additional length stabilizes the piston and prevents cocking
✅ Helps reduce delayed engagement and clutch slip in the 4L60-E family
💡 What is a pinless accumulator piston kit used for in automatic transmissions and why pick this one?
Handy to fix shift quality and prevent fluid loss in GM automatics.
1) Restores smooth engagement in the 4L60-E family with sealed bore
2) Eliminates pin bore leakage thanks to pinless design
3) Uses dual seals for long life and reduced wear