Hi, I am Garrett Glaze. I co-own a shop in Tulsa, OK and have recently recieved a surge of 6l80/6l90 based vehicles that have came in for transmission related issue due to poor tuning and craftsmanship from another shop. I have 2 right now that I need a little help on.
1. 2008 G8 with a maggie and 6L90 swap: I was in the process of tuning this particular vehicle and fixed a lot of initial issues with the trans, but what I am running into now is the converter not wanting to lock at WOT. I have tried many different regular gain and offset settings, made the ramp much more aggressive, and increase the TCC adapt pressure. When making a 2-4 gear pull, there is zero TCC psi until 4th gear, and it lowers to slip from ~220-250rpm down to 120rpm. We dropped the pan and replaced the filter and filled the trans already, and I am thinking that there is previous internal damage since the converter was reused from his original 6l80 that burnt up the clutches and wiped out the pump. I am not sure if it was flushed properly either. So we are planning to get it back in the shop to install a zl1 converter and zip kit, but my question for you guys is regarding the Tehcm and 80 to 90 swap. Is there anything that I need to do on the tuning side to look at? I will post a tune and log file when I get back to my tuning laptop.
2. We have a 2015 silverado that is getting a used 6l80 (2015 model as well). The old 6l80 is trashed (metal from the converter everywhere) so we can't swap over the tehcm/tcm. Being that they are out of the same year, will a dealer reprogram be needed or can you use HPtuners and write entire since its the same OS and year?
Thanks in advance for the help!
Garrett Glaze