W124 doorlock stiff
 

I recently replaced the driver door actuator and can’t seem to loosen it up to work with the key. It’s just too tight to use with the key. Need to open back foot then manually lock driver door for everything to work. Is there any tricks to make this work? I don’t see anything in the way that would cause it. Can I lube the actuator?

Sounds like a bad new actuator. I've never encountered it. Is there any chance the rods could be installed incorrectly or are bent?

Good luck!!!

Might be the lock barrel in your door thats sticking .Can you try it without the actuator .