Installed a yank 3000 stall (slp spec unit) into my Buick GS. It shudders when trying to lock under light throttle. I've increased the lockup speeds to 50 min and up from there. On the DC tables i've tried setting them to 100 and 50 respectively, all it does is bang engage bang disengage. So i tried different values 80 and 40, same results. I then stuck the stock tables in and does the same thing under like trottle lockup, apply apply locked shudder at which time i let out of the throttle. At highway speeds, 60-70 it locks up fine, no shudder. Last night i took it to the guy who built the trans for me (hard parts etc.) he said it doens't feel like the TC. We can manually lock it with the tech2 and it works perfect. Only thing he noticed was the slip rpm, it would read masive negative numbers like -700 etc. Right now i have the DC tables set at 100 max and stock min, it works, not perfect but i get hardly any shudder, if any, at light lockups. Anybody have any ideas for me? I bought this converter 2 years ago and just installed it, i doubt slp would help me, besides they know SHIT about wbody cars.