Welcome to the forum!
Try putting the stock tune back into the truck and see how it runs. You might need someone with a Tech2 scanner to check the codes.
I bought some of the R9 hose after corrosion ate my fuel lines about 10 or so years ago. I went from front to back with the hose. I've run bio diesel through it. Still going strong. I also replaced the return lines also. 👍
LOL. I was using it to pull down some trees that were hung up.
When I shifted from 4L to 4H I was not in neutral. When I realized that I quickly shifted the Allison into N but the transfer case didn't seem to shift. The whole truck then just stayed in N. My fault as I knew I should have been in...
Well. @Lennydmaxguy hit the nail on the head. I dropped the front drive shaft, took the encoder motor off, manually shifted the transfer case (counterclockwise) 2 clicks until it didn't go any further, took the encoder motor apart, lifted out the big gear and rotated it clockwise about an...
I think you are right. Issue happened when I was going from 4L to 4H. I had just shifted into N and then everything stopped. I gotta figure out which way 2H is on the transfer case.