Lock cylinder
 

My drivers side door lock no longer works with the key. I have squirting lube into the keyhole, but to no avail. Does anyone know if the cylinder itself is replacable, or do I have to replace the entire handle?

I'm pretty sure you can replace just the cylinder (on your model I'm not 100%)...but it isn't cheap...if you want to use the same key you have now you'll have to go through the dealer and it can run into $$$...another option is to buy a used one and be required to use a different key for that door...cheaper but maybe not efficient...you might just want to put a keyless system in...I've heard of taking out the tumblers and filing them down to some success though I've never tried it...I'm sure someone on here can be of more help than I...best of luck...

You might be able to swap it out with the one on the passenger side.

I had a trunk lock stuck too. I use penetrating fluid and soaked it for a few hours. Then some tapping with a wrench to loosen things up. After an hour or so of patient tapping and turning with the key (no forcing) it came free. Some ATF to lube it up and its been fine ever since.

I've used silicone (when dry lube wasn't readily available)...teflon...graphite as lubricants for my locks all with a good bit of success...lube the latches too...using the key slowly does help work the lube in...I forgot about switching it out w/passenger's side...but my mentality is to fix what's broken and not just move it...best...

OK. One more question. What is involved in removing the lock cylinder? Is it something I can do without removing the entire handle?

I forget exactly what you do...but if its like my w124 300e open the door and on the side there is a cover that hides the bolt that holds in the cylinder...its on the same plane as the cylinder...unbolt it with an allen key...and slide out the cylinder...best of luck...

Open the door and look at the strike side. If you have vacuum locks there will be an oval plug and a smaller round plug beneath. Remove both. Behind the oval plug is the connection for the vacuum lines; disconnect these. Behind the round plug is a set screw (allen head); loosen this, and with the key in the lock turn the key until you feel the cylinder come free. Very easy. regards,
Mark

Thanks, guys.