Driver's door lock stiff (87 e30)

[JHahn22@xxxxxxx]

Hello all,
The car in question is an 87 325i 4 dr.  The all the gizmos in the door locks 
seem to work electrically. However, unlocking the driver's door has always 
been very tough.  Sometimes you have to wiggle the key the other way first, 
and even then, there is a lot of resistance to turning the key, and the 
action feels very "heavy".  It feels like something is too tight or needs 
lubing perhaps.  That was when it lived in texas anyway.  The car is now 
living in NJ in the cold.  My dad broke off one key in the lock before it got 
real cold, and then he said that yesterday it froze up completely.  They were 
able to unlock the other doors from the trunk lock or passenger door, but 
until it warmed up the driver's door lock wouldn't budge.  They said they 
couldn't even unlock it from the inside.
I can't do the work on this from TX, so I need to tell them what to lube or 
replace in there.  They have the bentley, and I can walk them through dis/ass 
of the door, but what are they going in after?
Thanks for the help as always,
Jake Hahn
95 318ti
College Station, TX

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