4L60E Transmission Issues
 

Alright here's what I've got. I've got a '98 Z28 that's got 112k miles on her,a mild cam, and a few other bolt on's that are irrelevant. I just picked her up for practically nothing. I've got it running great now, and took it for a quick cruise to see what it would do. It makes the transitions from N-R and N-1 just fine, makes 1-2 fine, and at about 25 mph in second it feels like it goes into neutral. However, from a dead stop it made it to 80 mph in third with no problems. When in 2nd, after it feels like it goes to neutral I let off completely and I can feel it lock back into second. According to my Snap-On Solus scan tool, the TPS is working alright, and there are no codes from engine or trans. Does anybody have any insight on this? Your help is greatly appreciated.

Re: 4L60E Transmission Issues
 

From a dead stop you were at wide open throttle up to 80? Did you check the fluid?

-Geoff

Re: 4L60E Transmission Issues
 

Yes, fluid is right where it should be when hot, is not burnt and is brand new. When I left for the first drive it always seemed like it went into neutral at a certain sweet spot, and if I let off and feel it go into gear, I get all over it and it burns the tires, but under light throttle it does the same thing. Does the TCM need to see throttle percentage separate of the ECM?

Re: 4L60E Transmission Issues
 

Also the fluid that I drained was not burnt, and did not have any metallic powder in it.

Re: 4L60E Transmission Issues
 

Thanks for the help guys, I ended up removing the valve body and applying air to the clutch apply passageways, and the 1-2 clutch pack leaks a little and the 3-4 clutch pack leaks A LOT...time to yank it out and put a 6 speed in it!