Weathering Landing gear

You can give the gear a wash. (that's very thinned paint)

Washes are the way to go for landing gear.
You can also try a chalk pastel wash.

Find the article on www.aircraftresourcecenter.com, the Tools n Tips section, Washes and Weathering subsection, Chalk Washes.

I use a wash as well. Here's a link to how I do it:
http://www.craigcentral.com/models/wash.asp

and here's an image of what it looks like.


Also, here is a very good link to a page on Swanny's web site that covers weathering:
http://www.swannysmodels.com/Weathering.html