I just recently noticed my frontend is trying to jump into 4wd when at low speed 10mph and below and I just jacked it up in the front and spun the wheel and what the clunking noise is the front drive shaft clunking because the diff is not fully dis-engaging. What might cause this? I was told it is common when used offroad alot to sometimes bend a fork in the diff is this true? What is the Fix or what should I look at?