Sonnax 700R4 77998-03K Pinless 1-2 Accumulator Piston 200-4R 700-R4 Transmission
New billet aluminum pinless 1-2 & 3-4 accumulator piston. In these transmissions, it is common to have poor shift quality, burnt bands or clutches due to accumulator piston wear. Repeated reciprocation of the accumulator piston causes wear at the piston pin bore interface.
Sonnax 4L60E 77998-03K Pinless 1-2 Accumulator Piston 4L65E 4L70E Transmission
Sonnax Billet Accumulator Piston Part Number: 77998-03K New billet aluminum pinless 1-2 & 3-4 accumulator piston 4L60E, 4L65E, 4L70E, 4L75E transmission GM, Chevrolet, Cadillac, Pontiac, Buick, Oldsmobile, Hummer Package includes one piston. Two can be purchased to replace both the 1-2 and 3-4 piston locations. Stock, these transmissions had plastic pistons that break, burning up your transmission. This piston is very easy to install and is recommended when doing any shift kit. The 1-2 can even be done if you just have the pan off for a fluid change. The valve body doesn’t have to come out for this to be installed. The 3-4 piston does require the valve body to be down. Check out our eBay store for great deals on shift kits and other transmission parts.