kidtriton,
obviously you have the experience, but how will the rear limited slip cause this?
If tscholl is correct, and the front tires are "crunching" during a hard turn, then I agree that there can be an issue with the engagement to the front diff thru the transfer case.
**As most 4x4 owners know, driving a 4x4 on dry pavement while turning causes issues (mostly bad) due to the fact that ALL wheels are now turning at different speeds due to the different turning radius they are experiencing. The rear wheels usually do not have that much of a turning difference since they are locked in a forward facing aspect, but the front wheels can't compensate enough through the front differential (which is an open type) when locked into the same speed input through the center diff as the rear diff. What happens is that EITHER 1) the inner tire is made to slip on the dry pavement (it wants to turns at roughly the same speed as the outer tire, which wants to turn faster because of the larger turning radius) or 2) hop & spin as the inner half shaft gets wound up, and then releases its energy (it acts like a torsion spring, which is also the cause for torque steering on front wheel drive cars). It all depends on how well the tires grip on the dry pavement. In any case, bad noises will be percieved from the front end**
The cure that is used for ALL-TIME 4WD vehicles is to use a Viscous Center Coupling (basically a torque converter type unit) which will allow slip between drive shafts between the front and rear diffs.
Whew...I know that was long, but I am surprised at how many people really don't know this process.
In any case, if the trnsfer case is not releasing its clutch mechanism, then I can see tire noise issues from the fron end.
Also, one other thought. On my '98 Exby, I can make a crunching noise when I turn hard and try to accelerate a little too fast. THe Exby's actually have quite a tight turning radius available for such a large truck, and the truck really wants to "push" forward, slipping quite a bit on the front tires, which are trying to turn the truck. Try see if the noise goes away while driving at different speeds (slower).