The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

gofast321 · 06-20-2021, 10:34 AM

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

06-20-2021, 10:34 AM	#1
gofast321 Registered User Join Date: Sep 2010 Location: Pittsburgh, PA Posts: 38	8L90 Swap Lockup Issues 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