I'm at my wits end with this truck. If I can't figure it out I'm seriously selling it and starting over. Seems like my probs started after going to the track a couple times earlier this year. I had a few launches that were very violent due too suspension issues. One person said my pass side front tire bounced about 6" in the air on one launch. I noticed that soon after it felt like my front end was binding up when I turn sharp. Seemed like it was in 4wd. So my philosophy is don't fix it until it breaks. So I kept driving it. Then at a pull in June I was making my second of two hooks that night and when I tried to build boost it got to about 2000rpms and popped out of gear, so I tried again, same thing, they let me make one more run at it and it finally popped a po872 code. So I thought trans. Nope. Trans works great, I drove it home that night with no issues. So I drop the pan, change the spin on, change the internal and everything looks fine. Fluid was perfect. Then I think maybe the transfer case. So I rebuild it, same problems. Someone suggests blocking rings in case. So I buy a used case with 16k miles on it. Same issue. After I got this case put in there I tried building boost in 4lo and it popped out gear then it wouldn't work at all in 4lo. Just says shift range inhibited. 4hi and 2wd work fine except for popping out of gear when building boost. I can roll out to 10-20mph hammer on it and it works great, shifts great, just like it should. I've noticed that when I stop somewhere and throw my shifter into park it takes a second for the P light to light up. Sometimes it rolls a few inches then slams in park. This only started about 2 weeks ago before I swapped cases. Can my front end b jacked causing this issue? G80? Trans? Nsbu? I'm lost. I can usually figure stuff out but this is frustrating. If anyone has any ideas I'm open to any suggestions. Sorry for the long post.