Well, if the brakes are adjusted correctly and the car pulls, then either the adjustment is not correct or there is a defect somewhere in the system (brake or possibly steering/suspension).
You have four wheel ends and one end is adjusted differently from the other three (four wheel drum).
During a full panic stop lock-up, what do you think could possibly go wrong? These are self-energizing brakes and three lock down before the odd one? That one loose wheel end is also going to cause the other three to work harder, overheat and wear more quickly.
A mechanic/shop that does this will open himself to possible civil (possibly criminal) liability.
Not yelling, just trying to inform.
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