Does anyone know what the 1-2 shift time spec is for a 4L60e? My 2005 van shifts slower from 1-2 compared to all other shifts. I monitor it on my torque app and I see that sometimes the 1-2 shift takes .8s where the 2-3, 3-4 shifts only take .3s.

Thanks.

 

My van is a 95 with 130k. It had soft lazy shifts too. Several aftermarket solutions for this. I thought about a Corvette servo kit, and like the idea of the Sonnax .490 boost valve. These two would have been a pretty easy install and probably solved the problems. You might look into them.

I ended up going with a Transgo SK4l60e shift kit. It's a little more involved but I'm happy with it. A stiffer pressure regulator spring boosts the line pressure. A washer and some other trickery goes in your existing servo to firm up the 1-2. It also has a little spacer that blocks the Pulse Width Modulation of the converter apply. This makes the torque converter lock-up feel like an extra gear but not harsh at all. A shift kit can be a fun project installing some springs and drilling some holes.

While in there I also replaced all the solenoids and the pressure switch for good measure.

 

Hey John, after you did the shift kit install what were the 1-2 shift times afterwards?