4L80E Billet Accumulator Plate Kit with Cover & Bolts

This is a billet aluminum accumulator plate that replaces the factory stamped plate in the GM 4L80E and 4L85E valve body. The stock plate seals the low/reverse and other accumulator pistons; over miles it can flex and let apply pressure bleed off across the passages, which shows up as soft or lazy 2-3 and 3-4 shifts.

Swapping in the solid billet plate stiffens that surface so the accumulators hold pressure the way they should. The result is a firmer, more positive upshift and better clutch apply under load, which is exactly what you want behind a truck engine or a mild build. It bolts into the same location as the original plate, and the required cover and hardware are included in the kit.

Fits GM 4L80E and 4L85E transmissions (MT1 / MN8), 1991 and up. Installation is done with the valve body off the case during a rebuild or a shift-improvement job. If you are already reprogramming the valve body with a shift kit, this plate pairs well with that work.