MrRosado

I got in touch with Richard and swap would require a new ECU wiring harness on top of the harness for the TCU, and a laundry list of other minor tweaks and modifications. Long story short can it be done yes, is it worth it no. At this point I think when the time comes I will just have the 6L80 rebuilt with parts that address the known issues and weaknesses of the 6L80.

Thank you for the feedback. It's greatly appreciated. To answer a few questions. My 6L has not failed. However, I am getting a shutter or shake after the truck is shut off. It doesn't always happen, but usually about 3 seconds or so after the truck shuts down. If a transmission replacement is in my future I just wanted to see my options. I wanted the 8L90 mainly for the fuel economy gains. I don't tow much, but the truck spends a lot of time in 4WD in the winter here. A friend of mine has 2017 1500 with the 6.2 and gets 21 mpg on the regular. Kinda sucks to get 17 mpg on a good day with my 5.3. Thanks again for everyone's input.

I apologize in advance if this is covered in a different topic. I've been researching to see if it's possible to swap the 6L80 transmission in my 2015 Silverado 1500 CC 4x4, 5.3 V8 with the 8L90 transmission. I haven't been able to come up with a definitive yes or no answer. "I'm sure if you throw enough money at something anything is possible". Asking because I have access to a 8L90 and wanted to know if it's a pretty straight forward swap, or is it more trouble than it's worth. If I could get some insight into what would be necessary to complete this swap it would be greatly appreciated. i.e. ECU updates, driveshaft adjustments, wiring harness, bell housing adapter, etc. Thank you in advance for your time in replying to this post. P.S. I am aware of the issues with the 8L90. Just looking for what it takes to make the swap happen and not a reliability comparison between the two transmissions.