Your adjustment procedure is a little off. Since the shoe assembly floats at the bottom, relying on drag to get a good adjustment is pretty inaccurate. The proper way to adjust a Bendix brake is to tighten the adjuster until there's a firm drag on the wheel when it's turned by hand, but not quite locked up, then back the adjuster wheel off one full turn. That's 10 clicks on the starwheel with the coarse teeth, or 20 on the fine-toothed wheel used with self-adjusters. Pay no attention to whether or not there's any drag- - - -the shoes center themselves when the brake is applied. With the bottom of the shoes free to move, one shoe can drag the drum even with a lot of clearance dialed in. Your temperature difference tells me that some of the brakes can't quite retract far enough to avoid dragging the drum with the brakes released.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!