Grease keeps the moving parts of vehicles, pumps, motors and heavy machinery running smoothly, yet it is one of the most misunderstood lubricants in any workshop or plant. Two tubes that look almost identical can behave very differently once they are under heat, load or water. Choosing the wrong grade leads to premature bearing failure, frequent re-greasing and avoidable downtime. This guide breaks down the main types of grease, explains what the NLGI grades mean, and shows how to match a grease to the job in front of you.
What grease actually is
Grease is not simply thick oil. It is made of three parts: a base oil that does the actual lubricating, a thickener that holds the oil in place like a sponge, and additives that fight rust, wear and extreme pressure. The thickener is what gives grease most of its character, so the type of thickener is usually how greases are classified.
The main types of grease by thickener
Lithium grease
Lithium-based grease is the workhorse of the industry and accounts for the majority of grease used worldwide. It offers a good balance of water resistance, mechanical stability and temperature performance, which is why most all-purpose (AP) and multipurpose (MP) greases are lithium based. For automotive wheel bearings, chassis points and general machinery, a quality lithium grease is the safe default.
Lithium complex grease
Lithium complex grease is an upgraded version that handles higher temperatures and heavier loads. It is a strong choice for wheel bearings on trucks and buses that run long hours in Indian conditions, where heat build-up is a genuine problem.
Calcium grease
Calcium-based grease has excellent water resistance, making it useful for wet environments, water pumps and equipment exposed to rain or regular washdowns. Its usable temperature range is narrower than lithium, so it is best kept to moderate-heat applications.
Specialty greases
For very high temperatures, food-grade requirements or aggressive chemical exposure, specialty thickeners such as aluminium complex, polyurea and clay (bentonite) are used. These are niche products, and most buyers only need them for specific machines named in the equipment manual.
Understanding NLGI grades
The NLGI number (from 000 to 6) describes how firm or soft a grease is, not its quality. Lower numbers are almost fluid; higher numbers are stiff. In practice:
- NLGI 0 and 1 — soft, used in centralised lubrication systems and colder conditions where the grease must flow.
- NLGI 2 — the most common all-round grade, used for wheel bearings and general greasing.
- NLGI 3 — firmer, holds well in high-speed bearings and where leakage or fling-off is a concern.
A common naming shortcut in the Indian market is AP3 and MP3, where AP means all-purpose and MP means multipurpose, and the 3 refers to the NLGI consistency. If you want a detailed comparison of those two grades, our separate guide on AP-3 vs MP-3 grease covers it in full.
How to choose the right grease
Start with four questions: How hot does the part get? Is it exposed to water? How heavy are the load and speed? And what does the equipment maker specify? For most cars, bikes and light machinery in Delhi’s climate, an NLGI 2 lithium multipurpose grease covers the job. For heavily loaded truck bearings or hot-running equipment, step up to a lithium complex grade. For pumps and wet areas, calcium grease earns its place. When in doubt, follow the equipment manual first and the operating conditions second.
Why the manufacturer matters
Grease is only as good as the base oil and additive package inside it, and low-cost greases often cut corners on both. As a Delhi-based grease and lubricant manufacturer, Petroblast produces AP3, MP3 and multipurpose greases with consistent quality for automotive workshops, fleets and industrial buyers across Delhi NCR and India. If you are unsure which grade suits your machinery, our team can help you match the right product to your application — simply reach out through our contact page.