Features and Benefits
- Eliminates concerns of forward piston damage
- Dramatically increased strength and reliability over the factory cast aluminum piston
- Can be used in both early and late transmissions
The General Motors factory cast aluminum forward piston frequently fails prematurely due to rough castings and high stress risers. Installing an aftermarket shift kit or having an aftermarket transmission calibration can make this issue even more dramatic.
The Sonnax 4L60/65/70-E billet forward piston correct this issue. This new piston corrects this failure by using ultra high strength billet aluminum.
This new forward piston has also been redesigned with added contours in the high stress areas to improve function and performance.
This part can be used in all 4L60/65/70-E's as long as it is used in conjunction with an aluminum overrun piston.
No machining or modifications are required to use this new piston.