Transfer case woes

Hi, my 2001 Bravada seems to be experiencing the same shutter issue as many of you have described in previous threads on this board. The dealer supposedly changed the fluid associated with this problem, although I don't know if they changed it twice as specified. The shuttering has significantly reduced, but still remains on those tight turns or pulling into a parking space. I have driven the vehicle 500 miles since the initial fluid change. Would a second change possibly fix the remaining shutter? Or, is there a posibility of internal damage to some of the parts? What have all of you with this problem experienced? What finally fixed the problem for you?

Had the problem with my 99 - I followed the drain/fill/drive 100 miles/drain/fill procedure. I haven't noticed it happen since.

Hi Biv,
What fluid did you use and where did you get it?