03 6.0l/4l80e combo in my 71 chevelle, cam change, and the 3200 convertor, perf tune, tranny seems to shift good, but at 35-40mph at light/to little throttle press. the trans will shift into OD then when I let off the gas it shifts out of OD, then when it goes back into lockup it really bangs/hits hard,kinda annoying really. IS this normal? Is it a norm for the lockup torq.?

Also, when I pull in down into what should be 3rd/drive(not OD) it doesn't seem to be any different than in 4th(OD) only when I pull it into 2nd does it change???? Is that normal? Thanx for any help!!!
Rick

 

Sounds like the converter is locking up so I would look into your tune.

 

Is this a stock LSx PCM?

 

It all came out of a 2003 express van, pcm/wiring went to speartech for workover,then to a local tuner for work/dyno.

Yank, thanx for chiming in. I was going to call but saw your closed this week. That's what I was wondering if the tuner caused it to shift this way somehow.
Thanx,
Rick

 

4l80E , Yank 3400 , 99 T/a, Car drives like stock, somtimes i forget its even got a stall , UNTIL i get in it , then its crazy. In my opinion, its 100% the trans tune.

 

Most 4L80 Operating Systms unlock the TCC under 5% throttle no matter how its tuned.