Hello everyone! Been a little bit since I’ve been on the forum but is good to be back. I’ve got a bit of an issue with my transfer case that has me dumbfounded. Or at least it has me confused on which way to proceed as I’ve read about several possible causes and solutions. First, the 4wd hasn’t worked on my 99 suburban k2500 7.4L vin J since I bought it. It has the 4L80e transmission that I just replaced with a used one this summer while I rebuild mine(which I still haven’t got to 
) and I believe it has the np246 transfer case. So, it hasn’t worked since I bought the vehicle but after replacing the transmission now all of a sudden it works except one little problem....it’s stuck in 4hi and will not come out of it no matter what I do. I haven’t tried to put it in anything but 2hi because I’m afraid it would just get stuck in 4lo or 4auto if I did. I have tried the R, N, D, N, R trick or at least I think I have but am unsure how fast I’m supposed to cycle through the gears or if I’m supposed to hold the 2hi button while doing so, I unhooked the VSS plugs and double checked that I had them plugged in correctly but it still will not go into 2hi. I’ve checked the case fluid and topped it off and that didn’t work either. So I removed the front shaft until I can get it fixed. Ever since the 4wd magically started working a few days ago(its been months since I replaced the trans) my Burb drives very strangely, even with the front shaft removed. At about 30 mph a noticeable shudder starts and persists until around 40 mph where it turns from a large vibration to a violent shaking and it feels like the wheels are literally coming off the ground. But it doesn’t do that all of the time, only after the vehicle is thoroughly warmed up( about 30 minutes). The steering becomes sloppy and seems to jerk itself to the left intermittently. It feels like 4wd steering when you turn at slow speed but the front shaft is removed and really sloppy, loose steering when turning at higher speeds. I can hear the shift motor operate and try to go into 2hi twice each time I press the button, sometimes violently, to the point that it lurches the vehicle some, especially when trying the R, N, D, N, R trick. Nothing I have done or can think of trying has helped it in any way and I need some guidance on where to start. I tried to purchase a new encoder ring but OReillys told me that there isn’t one for my truck. I find that hard to believe, I think they just don’t carry it. The part number I keep coming up with is an AC DELCO 600-120 but they said that that part number is only for 2003 to 2007 or maybe 2006. Not important. I had some other issues directly prior to the 4wd magically coming alive that may or may not help diagnose my problem. I was in the middle of a 2 hour drive to St. Louis when I busted a brake line and had to turn for home. The reservoir drained almost completely dry brfore I noticed the light on the dash and my pedal going to the floor. I was able to buy fluid and lump her home but I’m afraid sucked an awful lot of air into the master cylinder. I fixed the brake line the next day and bled the brakes. After fixing that I took a drive and everything was fine until it started the shudder I described earlier. Oh, forgot one detail, when I backed out of my driveway one of the wheels fell plumb off cuz I was lazy and didn’t take wheels back off to check torque on the wheel spacer lug nuts when I repacked hub bearings with grease a couple months ago. Please help, I’m at a loss and this old girl is a show truck of sorts and I’m missing shows while she’s out of commission. Thank you. Here’s a pic of my old girl just because 
) and I believe it has the np246 transfer case. So, it hasn’t worked since I bought the vehicle but after replacing the transmission now all of a sudden it works except one little problem....it’s stuck in 4hi and will not come out of it no matter what I do. I haven’t tried to put it in anything but 2hi because I’m afraid it would just get stuck in 4lo or 4auto if I did. I have tried the R, N, D, N, R trick or at least I think I have but am unsure how fast I’m supposed to cycle through the gears or if I’m supposed to hold the 2hi button while doing so, I unhooked the VSS plugs and double checked that I had them plugged in correctly but it still will not go into 2hi. I’ve checked the case fluid and topped it off and that didn’t work either. So I removed the front shaft until I can get it fixed. Ever since the 4wd magically started working a few days ago(its been months since I replaced the trans) my Burb drives very strangely, even with the front shaft removed. At about 30 mph a noticeable shudder starts and persists until around 40 mph where it turns from a large vibration to a violent shaking and it feels like the wheels are literally coming off the ground. But it doesn’t do that all of the time, only after the vehicle is thoroughly warmed up( about 30 minutes). The steering becomes sloppy and seems to jerk itself to the left intermittently. It feels like 4wd steering when you turn at slow speed but the front shaft is removed and really sloppy, loose steering when turning at higher speeds. I can hear the shift motor operate and try to go into 2hi twice each time I press the button, sometimes violently, to the point that it lurches the vehicle some, especially when trying the R, N, D, N, R trick. Nothing I have done or can think of trying has helped it in any way and I need some guidance on where to start. I tried to purchase a new encoder ring but OReillys told me that there isn’t one for my truck. I find that hard to believe, I think they just don’t carry it. The part number I keep coming up with is an AC DELCO 600-120 but they said that that part number is only for 2003 to 2007 or maybe 2006. Not important. I had some other issues directly prior to the 4wd magically coming alive that may or may not help diagnose my problem. I was in the middle of a 2 hour drive to St. Louis when I busted a brake line and had to turn for home. The reservoir drained almost completely dry brfore I noticed the light on the dash and my pedal going to the floor. I was able to buy fluid and lump her home but I’m afraid sucked an awful lot of air into the master cylinder. I fixed the brake line the next day and bled the brakes. After fixing that I took a drive and everything was fine until it started the shudder I described earlier. Oh, forgot one detail, when I backed out of my driveway one of the wheels fell plumb off cuz I was lazy and didn’t take wheels back off to check torque on the wheel spacer lug nuts when I repacked hub bearings with grease a couple months ago. Please help, I’m at a loss and this old girl is a show truck of sorts and I’m missing shows while she’s out of commission. Thank you. Here’s a pic of my old girl just because 
