Hi, new here. Tried searching this problem first, no luck. Here it goes. I swapped out the 4l60e 4x4 that worked fine, with a 4l80e due to horsepower gains. Transmission is perfect, but 4x4 isn't working. The light blinks and goes back to 2wd. Now dash says service 4x4 after some time on the road. I have a few thoughts... tccm relearn and how? Swap the tccm with a 2500 version? Swap the push button switch as well with a 2500 version? Transmission is a brand new stage 4 built by gear star and bench tested. Came with transfer case to match. I told them np8 but... not sure if they could do that. Consider everything new including actuators. But what remains stock is control module and dash push button switch. Any feedback would be appreciated.