Is the gallon drum worth it over aerosol cans?

If you use WD-40 regularly, yes. A gallon covers about 600 to 1,000 square feet, so the cost per ounce is far below cans. You will need a spray bottle or pump to apply it.

Can I use it on electrical equipment?

WD-40 is a non-conductor with a dielectric strength of roughly 44,400 to 47,800 volts, and it is commonly used to displace moisture from electrical and electronic parts. Let it dry before powering equipment back on.

Does it work as a long-term lubricant?

It lubricates and protects metal against moisture and corrosion, but it is a light oil with a film of about 17 microns. For bearings and high-load parts, use a dedicated grease.

What temperature range does it handle?

It operates from -10°F to 200°F and has a freeze point of -63°C (-81.4°F). It is not suited to high-heat applications such as oven or exhaust parts.

Will it damage paint or plastic?

WD-40 is generally safe on metal and most plastics, but it can stain porous surfaces and soften some finishes. Test a hidden spot and wipe off excess before painting.

When is the price lowest?

Bulk drums like this one tend to be cheapest from industrial suppliers rather than big-box stores. The current best new price is $32.76 at JRM Supplies as of November 6, 2026.