Squealing Tires and Squirrely Steering

Good to know. My other car is an outback so familiar with the issue there and wasn't sure if a similar issue could arise when in 4WD.

 

I also have a problem with my front tires squealing. Happens when I make tight turns into parking spots or 90 degree turns at low speed. I have had ball joints replaced and alignments done. Tires and pressure are good. I could not find anything wrong and neither could the mechanics. I finally wondered if it had something to do with the 4 wheel drive. NO the 4 wheel drive was not on but maybe it was sticking. I turned on the 4x4 for a little while and shut it back off. The problem went away. After a while the squealing comes back again. I think the 4x4 is slightly engaging by itself. Every time I start to have a problem I just drive with the 4x4 for a little bit and shut it back off. This always corrects the problem.

Is the 4x4 actuator going bad? Can it slightly start to engage by itself and cause this squealing?