About 8 months ago I had to replace my 1999 Toyota Landcruiser Transfer case with a used 2001 Lexus LX470 transfer case. In the past couple of months, on two occasions, my vehicle inadvertently shifted into 4W/Low gear while slowly turning left into a parking spot. The High/Low gear shift lever however was still in the High position. The Techs who replaced the transfer case have since gone through it and cannot figure out what caused the issue since they cannot get it to duplicate the problem. Do you have any Idea as what may have caused this issue?