Rear wheel jammed

I was driving my Tacoma in 4X4 going ice fishing then I stopped and put in the rear gear. All of a suddend the left rear wheel blocked.
Put in front gear all OK back to rear gear jammed and the OK.

Any idea why?

 

Sounds to me like a brake problem, drum brakes auto adjust out when you brake in reverse. I would check the adjustment mechanism.

 

Thanks I'll check the brakes

 

Check to see if the shoe material separated from the metal shoe. It might have been wedged between the other shoe and the drum.

Also, Rear auto brake adjust on some vehicles occurs when the e brake is applied

 

Pull the drum sounds like some parts have come off inside like the shoe hold downs.