Left rear brake drum gets hot

I have the same issue. Had the car out the Sunday before for a 1/2 hour jaunt. Pulled in the garage and smelled something hot. Sure enough, the left rear wheel is rather warm. I've changed nothing to affect this, all worked fine for years after the swap. Moser axles w/green bearings and I have 11 x 2" drum brakes. Haven't had a chance to look at it yet, possibly this weekend. I'll post what I find.