Another potential bind spot would be the CV joints of the front axle, especially if this "lock up" is only occurring on sharp turns. There are spider gears in the transfer case as well, but I would expect you to be hearing a lot of noises from that on any kind of a turn when the two axle shafts have to spin at different speeds.

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2016 F15 x35i
2014 F32 428i


2004 E46 325i sold at 123,600 miles
2002 E53 3.0 sold at 388,801 miles
2001 E46 325i sold at 66,000 miles


1970 Firebird Under restoration