I have about 400 miles on my new build. I got a rebuild 4l80e from a shop with a 3600 stall speed that was suggested by Tsp. It has a trans-go hd shift kit in it supposedly. The more I have been driving it the less power it seems to have from the trans. Example, after the dyno tune it would smoke the tires until I let off. Now it won't even break them loose. I took it to a different trans shop to have them test drive it. They swear it is the TC failing. Said I probably got a junk one the guy was needing to get rid of. When I contacted the original builder he will not warranty it because he says it has to be my tune that is making it fail. Could someone look at my trans tune and see if I messed it up somehow? I have a new TC being built to match my engine specs. Any help here would be great. 5.3 bored, flattops, .629"/.615", 111 LSA cam, longtubes, 862 Heads worked
Thanks in advance