I get a groaning sound that appears to come from the rear of the vehicle when I take slow (5 mph) sharp turns. The sound is very human and does not sound metallic. The car is a 2001 with 130K on it. I have had the tires, rear end, transfer case, and brakes looked at and no one can find any issue.
If it has posi-trak / locking rear gears the oil addative concentration could be lacking after all these years of mini top-offs gradually diluting it.
Worst case is you have a positrak clutch problem.
or an ex wife in the trunk.
I have changed the fluids, with special additive, twice–no change
Try having them look for the groan instead of checkng a specific assembly. Groans of this sort often come from bushings. On 9 year old vehicles they’re actually quite common, as the rubber bushing dry up and shrink.