lxcoupe

iTrader: (9)

Have about 2k daily driven miles on my craigslist 80e, Trans Go HD2, and Circle D 2B 258mm. Bone stock 5.3L motor with segment swap. The trans shifts perfectly, other than a small problem which I believe is tuning related (it has done this from the beginning of the swap). At WOT in 2nd gear, at ~4k rpm, it feels like the clutches disengage for a second or two, then re-engage. It definitely feels like a tuning issue. I do have TM removed and shift times set to .200 other than that I have not messed with anything. Any ideas? I found this video on youtube that is vaguely similar:

Fast355

Sounds like it might be torque converter clutch related.

lxcoupe

iTrader: (9)

As in a mechanical problem or tuning?

GMCtrk

iTrader: (27)

sounds mechanical to me

lxcoupe

iTrader: (9)

Hmmm, I've read a misfire can mess with the tcc. I wonder if pinging could do the same thing? I've been putting junk 87 gas in this thing since day 1.

03sierraslt

iTrader: (22)

Post up your TCC table. Or just the whole tune.

Fast355

I am thinking tuning as every stock 4L80E tune I have seen locks the torque converter in 2nd gear and then unlocks it again before the 2-3 shift or keeps it locked.

03sierraslt

iTrader: (22)

Sounds tune related to me also.

lxcoupe

iTrader: (9)

Thanks for the replies guys, I do appreciate it. I should mention that other than this issue the trans is literally flawless. It has never seen north of 140 degrees and never once clunked/ slipped did anything that would suggest something mechanical. It could be VSS related? The speedo as well as my Aeroforce are dead accurate though when compared to an iPhone GPS signal. Here are my TCC and VSS settings. I also read that when I do the segment swap I needed to swap over the Trans diagnostics? I don't remember if I did that.

lxcoupe

iTrader: (9)

This is 100% what it does. It doesn't feel violent, and the 2-3 shift feels real good. It just feels like someone cut the power for a second or two.

Also, how do I attach a file to the thread?