My son loves his 2000 S70 but today he wasn't feeling it so much because as he was driving out of the school parking lot, his right rear wheel locked up hard.

When he put it in reverse, the wheel turned freely, so he shifted it back into drive and tried it again. It worked for a bit then locked up again.

He tried backing up a second time and that seemed to fix his problem until he went over a small bump in the road and the wheel locked again.

It was like a monty python skit, he'd get a little way down the road only to back up, drive forward, do it again and again until he got home.

I thought he would have tried to drive home in reverse, but he didn't thank goodness.

At first I thought this was a stuck caliper but after what he told me, I am thinking it is something else.

Could it be a bearing? I don't hear any grinding or clicking noise like a bad bearing would make.

Does the back rotor house the emergency brake linings?

Is it possible that the emergency brake could be the problem?

I would be surprised because I have NEVER had an emergency brake that worked as well as this wheel gets stuck.

I live in the northeast and today is a horrible weather day with rain and thunder. I don't have a garage so I haven't been able to take it apart yet.

I am looking for some pointers on where to concentrate my troubleshooting before I get stsrted.

Appreciate any feedback, Thanks!