Transfer Case

[DenaliMCD]

I haven't taken the car in yet to have it fixed (because it will have to be towed) but i was coming home on New Years day and i pulled out onto a road with normal acceleration and first gear was fine, then it jerked slowed the car down and i heard a load cracking noise.. I pulled over and checked everything and then started to go again after i found nothing. when i accelerated again, first gear was fine until it never shifted to second and held it at 6ooo rpm and then shifted fine into second and so on. I pulled over again and the Service Engine Soon light came on as i did so. Reverse works perfectly and forward took a lot of throtle to get it going but even then it maxed at like 5mph. I opened the door and just put it in gear and i heard a bunch of clunking like the transmission was spinning something it had broke off, i haven't looked underneath it yet but i was able to tow it home fine by just putting the tranny in neutral(No Neutral on the Denalie for the transfer case) So its sitting outside my house with 60k miles on it and already has drive train problems and its never been worked or abused, seem right to you? anyone else have this probelm, and if so, how to fix and any tips
Thanks DenaliMCD

[FLTraumaRN]

Your planitary gears ar broke in the tranny. these gears are weak and gm knows it

[DenaliMCD]

Not sure i am going to repair this, called the GMC dealer and they said that it was out of warranty and that i am stuck with it. I have heard that they replaced the tranny that is in the 2001 denalis in 2002 with a stronger tanny, even though this one was also designated as a "Heavy Duty" tranny. I am thinking about just getting a new one.

It feels more like the programing in the tranny is off than the planitary gears. it just doesn't seem to engage all the way or shift when it is supposed to. I can put it in first and it works then second and it shifts but if i just put it in D it doesn't work anymore. It did but then that clunk... Oh well maybe it is time to just buy a new one. although 50k for a car that breaks at 70k miles doesn't seem like it is worth it.
I guess thats why there are discounts