i dont know if it would help you all. but i was having the same problem with my 4l60e. so when my hptuners showed up that was the first thing i looked into, was the shift points. for some reason it was calibrated to the point that only one of the two variables(speed/rpm) was being met. so i dropped them both down just a fuzz and i didnt have the first problem after that.

 

I'm scared to ride in your car now because I'll probably end up with a procharger on order within hours of that experiance. But I'm willing to take that chance.

Tuning issue is very possibile. Does this happen on your street tires as well? The taller tires you were on today could have been growing even further by the 2-3 shift.

What's the rev limiter set at? What's the shift point? With a setup like yours, I'd want a good 200rpm between the shift point and the rev limit.

Did you make some passes with the shifter in OD (4th)? Seems that line pressure drops on the 2-3 shift with the gear selector in 3rd as it brings the overrun clutch on and taps the 3-4 clutch pack of fluid pressure. If all your passes today were in 3rd, then I'd try putting it in OD next time out.

 

ok I though I posted this but it got gone ?Ok I here about the bouncing off the rev limiter at wot all the time in the post , And I have a question not about what the pcm is programed to do but what it actually does , Has anyone ever actually had a scanner hooked up in data mode and watched to see if the shift was comanded ,I know I had a guy once complaining of the same issue at wot with and without nos , he kept saying its was the transmission because he had it tuned by two different people , I didnt have a scanner available at th time but did have a schafer shifter (its a box with a harness you plug directly to the trans and turn the solinods ect off and on manually with the pcm unhooked from it )we went through the gears on the interstate WOT aand with nos and in each case when i turned off both solinoids the trans shifted right into third , So in his case it was proven to be a programing issue , Never saw him again so do not know what he came up with ,
The other possibility and this is assuming the command was made and the 3-4 clutches are good is solinoid flooding , This can occur two ways one is for those of you who have the line turned way up you could be simply sending so much volume to the solinoids at wot that they cant vent fast enough keeping the valve stroked and not allowing the 3rd , Another way this can happen to is when a shift kit is installed and the wrong hole drilled ,
If you really want to fix this problem for good follow the following steps
1- get the car hooked up to a scanner in data mode (snap on or something equivalent )run through the gears while having someone watch the comanded shift , Did the shift command occur?If not back to the tuning board ,
2-If the comand was made then call around and try and find a shop with a schafer shifter (Im thinking of building one to market just for a 4l60e ?)and see if you can get them to go through the gears with you WOT make sure they have the line set at max ,does it shift , if so then you do have a problem still with the electronics or tuning though most likley if it didnt shift when the pcm comanded it it wont in this test either.
3-if the shift did not occur with the schafer or the pc comand and you know the 3-4 clutch is good , I would suggest the following replace the transfer plate (plate between valve body and case) with a new one from transgo and replace the solinoids with replacments from a company called fitzall , These solinods have large vent area and are less likley to get flooded and this should fix the problem ,

And when doing tuning remember you can have to much pressure , Thats why we only suggest increasing the factory preasure by turning the pcs torx bit screw no more than 1/4 turn clock wise ,and leaving the preasure part of the tuning alone .Doing it this way assures you wont get excessive amounts ,
Hope this is some helpfull information .
www.performabuilt.com

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I haven't had mine hooked up to the scanner. I guess I need to, as I want to get what I can out of it. I have 4.11 gears and have my 2-3 shift set up to shift @ 55 mph and 5900rpm. Rev limiter @ 6300. It does ok on motor, feels early on 1-2, late on 2-3 and yes I have to shift into OD but have TM on the OD still, BTW I leave the line in OD. Bottle is same, but hits limiter on 2-3= I guess it could be tuning. Part throttle 2-3 shift is nice and crisp/ quick.

 

Wow that is what happens with mine. I to have 411 gears and the 1-2 does feel early. RPM i was told the rev limiter was set at 6800, and was told the shift points were just set to stock and that rpm and speed would determine my shift points. I did try it in od and it worked fine. That time i was on the spray, it shifted into od which i no is bad. Still managed a 10.8.

 

i have had hptuners running and logging the trans while at the track.
i can see the commanding of the --3--, then it lags. for up to 2sec before the actual shift occurs. 3

again, this only happens at WOT.
part throttle is perfect. even when getting spirited, playing around.

i can send u a log/scan showing the activity if u like.
i dont believe the tranny needs a complete rebuild but something needs to be addressed. i just cant seem to find out what.
i've dropped rpm shift pnts,
changed mph, points,
raised limiters, etc.

h/c, 3800stall, spray track for track use.

but adding something else to the mix is that if i leave off idle. the 2-3 hit is crisp, immediate.
but stalling it up the lag/hesitation prevelant...

opinions?
discuss?

thanks