8L90 Swap Lockup Issues

[gofast321]

Hi everyone. I just finished an Gen V L83 / 8L90 swap in my 1988 Suburban. I love the swap; power and gas mileage are both awesome!

My question is... When coming to a stop in the truck it feels like the torque converter lockup doesn't let go until the very last second and causes a little bit of a lurch in the truck as it stops. Has anyone else had this issue in their 8L90 swaps? Is this expected behavior from this trans? If not, does anyone have a suggestion on what I should start looking at (my transmission knowledge is terrible)? I do have the torque converter control wire from the harness hooked up to the brake light switch in the truck to show the ECM/TCM 12v when I step on the brake.


Thanks in advance for the help.


Chad