So, I have a friend with a 2008 Silverado 4.3 auto and we were finally able to access the E37 ECM with success. The only problem i'm having is the fact that I cannot calibrate the tire size in the Gear/Tire Calculator. I'm attaching the file, hopefully someone can help me out. I've never actually had to manually calc out the vss pulses and mile, so if anyone could help me out to calibrate 35" tires w/ 4.56 gears I would appreciate it. Or at least help with a thread link to help do it myself. And with this newest beta version, things seem a little different.