This is the all you needed to know page about your Leatherman maintenance

Rust and Corrosion
All Leatherman Multi-tool products are manufactured from 100% high-grade stainless steel. (Exception: The Leatherman screw bits for the tool adapter are made of tool steel.) But stainless steel is not rust proof; it is corrosion resistant. Depending on the mix of metal alloys, stainless steels may be highly corrosion resistant and relatively soft (like kitchen flatware), or they may be somewhat corrosion resistant and quite hard. Leatherman products are fabricated from the latter type, so your Leatherman tool components are strong and the knives retain a sharp cutting edge. Consequently, corrosion can occur in the absence of proper maintenance. Your Leatherman product should be cleaned, dried and re-oiled periodically to inhibit rust and corrosion. This is especially true if you use your Leatherman in a damp or marine environment. After cleaning, re-oil pivoting areas with a light machine or penetrating type oil (such as WD-40). Buff stained surfaces with a polishing cloth or non-metallic abrasive (e.g., Scotchbrite pad or soft bristle brush).

Blade Sharpening
Leatherman Multi-tool  products feature knife blades that may be straight-edged, serrated or both. Sharpening methods vary depending on the type of knife in your Leatherman product. Note that Leatherman serrated edges should not be sharpened in the same manner as straight edges. Leatherman straight-edged blades can be sharpened using any standard equipment, including whetstones, rods and various kits. To sharpen a Leatherman serrated blade, be sure to use a sharpening system specifically designed to accommodate serrated edges. A proper sharpening method will maintain the curvature of the serrations. Sharpen Leatherman serrated blades only on the edged side; sharpening the flat (back) side of the Leatherman knife will cause the serrations to wear away, reducing the knife's effectiveness.

Cleaning Method
Depending on what your Leatherman Multi-tool has been exposed to, there are several cleaning methods to consider.

If your Leatherman Multi-tool has been exposed to salt water or marine environments, it should be thoroughly rinsed in fresh water, dried and lubricated with a water-displacing product. If stains or rust spots appear on your Leatherman, refer to the Rust and Corrosion section above for removal tips.

If debris or sticky substances have accumulated between the blades, your Leatherman Multi-tool may also be cleaned in a mild solution of detergent and water.

To remove tar and similar substances, clean your Leatherman Multi-tool with turpentine or other mineral spirits. Do not use chlorine products.

After cleaning, dry your Leatherman Multi-tool and apply a light machine oil or a water-displacing product (WD-40) to force out moisture trapped in the joints. This also helps protect the tool from further corrosion and sticking.

 Now you know how to maintain your Leatherman Multi-tool check out out range: