PeachParts Mercedes-Benz Forum - View Single Post

tinypanzer · #10 04-13-2010, 04:36 PM

I guess we can agree to disagree on this matter, though I'm still curious about the MB lube stuff you mentioned.

But the fact that MB actually says to use powdered graphite in the owner's manual is good enough for me. Plus, I've been using only powdered graphite in locks for years and I've never had one gum up. The only exception to that is if you spray oil into a lock that was originally lubed with graphite or vice versa. Basically, once you pick a lubricant you'd better stick with it. Mixing lubricants, especially graphite and oil is a sure way to make a sludge.

I don't like using oil on door locks for a few reasons. First, oil attracts dirt. Every time you insert the key, whatever pocket lint that was on there or whatever will get in the oil and stay there. Also, if you live on a dirt road or in a dusty environment using oil in your door locks will very quickly become an issue. You basically wind up having to oil the lock all the time in order to wash out the crud that the oil attracts. Messy. The only time I'd use WD-40 or similar is on a frozen padlock that's been in the weather. For that it works well, but again, expect to have to re-apply frequently.

Graphite works because it absorbs some atmospheric moisture and this moisture gets trapped inside the graphite's lattice structures and acts like ball bearings. It doesn't attract dirt because it's dry, and it gets into little crevices and actually keeps dirt out by simply taking up the space that the dirt wants to get into. As far as corrosive effects, you only have to worry about aluminum. Steel and brass aren't an issue.

Honestly, I think that most of the bad rep that graphite gets is due to people mixing it either knowingly or unknowingly with an oil based lubricant. I've never had a lock that used ONLY graphite give me an issue. Ever.