This is a custom made servo piston and cover made of billet aluminum the pieces are high quality with an improved piston seal and a different spring. The second kit is called the 'Super Servo' that handles the overdrive and converter lockup it runs $77.33 at OPT. I guess you can score one on eBay but I would recommend going with the OPT guys that's where I got my stuff. The 'Corvette Servo' kit is relatively cheap and the guys at (OPT) Oregon Performance Transmissions ( ) have the kit at $18.99. This is an easy modification to do and the improvement in shift quality is miraculous. There are two servo kits: one is for the 1-2 and 2-3 shifts (the Corvette servo) and the other is for the 4th shift and converter lockup. not slipping but just taking its sweet time engaging second. My truck also suffered from what's known as a 'slide bump' first second shift the tranny begins its shift and sort of hangs in limbo.

I have read about the Torque Management system that's integral to the engine control computer that basically hamstrings the engine during various phases of driving and during transmission upshifts. I have to wonder if the design engineers didn't have some marketing mantra to design their full-size trucks to shift and ride like some ultra-cushy kind of limo. I've ridden in Caddy's that have a more robust shift than the 4L60E in my truck. But one of the things I just couldn't stand was the truly wimpy way the thing shifts gears. When I bought this truck last summer it was a nice upgrade from my '98. I just got done putting in both the servos in my '06 Sierra. I was getting ready to put a post up about the Corvette servo mod.

Corvette servo 4l60e pickup