The right grease for pins and bushings is an NLGI #2 extreme-pressure lithium grease with molybdenum disulfide, chosen for its ability to stay in place under shock loads and resist water washout.
When a loader bucket pin starts to squeak or a crane slew feels rough, the fix is rarely a mystery—it’s usually the wrong grease or not enough of it. Pins and bushings take pounding, dirt, and temperature swings that would wash out a standard chassis grease in hours. Using the right grease for pins and bushings means picking an EP (extreme-pressure) NLGI #2 with solid lubricants that won’t squeeze out under a 20-ton load.
What Makes Grease Work for Pins and Bushings
The job is simple: keep metal-on-metal surfaces separated under massive pressure, slow movement, and frequent shock loading. Standard multipurpose grease lacks the film strength and adhesion. The grease for pins and bushings needs three specific properties:
- NLGI #2 or 2/3 consistency — thick enough to stay put, not so stiff that the grease gun fights it in cold weather.
- Extreme-pressure (EP) additives — typically molybdenum disulfide (moly) at 3% or 5%, which forms a sacrificial layer that prevents metal welding under peak loads. Caterpillar’s field guidance, widely followed in the industry, calls for 5% moly grease for pins and bushings.
- Tackiness and water resistance — the grease must cling to vertical surfaces and not wash out when equipment works through mud or rain.
The same characteristics that protect earthmoving pins also apply to agricultural implements, crane pivots, track rollers, and suspension bushings—any joint where steel rides on steel under heavy load.
The Best Grease for Your Equipment: What the Specs Actually Mean
Not all NLGI #2 greases are equal for this job. The table below shows the key differences between current products designed specifically for pin and bushing applications. Comparing their published specs tells you exactly what you’re buying.
| Property | Penrite Pin & Bush Grease | CGN Pin and Bush Grease |
|---|---|---|
| Base & Thickener | Clay-based | Lithium soap |
| NLGI Grade | No. 2 | 2/3 |
| Solid Lubricants | Not specified | Graphite + MoS₂ at 16% |
| Timken OK Load | Not published | 22 kg |
| Operating Range | Not published | -20°C to +140°C |
| Primary Use | Rubber/polyurethane suspension bushes and pins | Heavy industrial pins and bushings, auto-lube systems |
| Special Feature | Safe for polyurethane; petroleum-free formula | Dropping point None; extreme heat stability |
Penrite’s clay-based formula avoids the petroleum base that can damage polyurethane bushings in excavator pins, a common failure point for owners who grab general-purpose grease.
How to Apply Grease for Pins and Bushings the Right Way
Good grease fails if the application method is sloppy. For pin-and-bushing joints on heavy equipment, the correct procedure is straightforward but often skipped:
- Clean the grease fitting — wipe off caked dirt before you connect the gun, or you push grit straight into the bearing surface.
- Apply until fresh grease emerges — pump until you see new grease squeeze out of the pin or bushing gap. Old, dark grease means the joint was under-lubricated.
- Cycle the joint — for a loader or excavator, raise and lower the boom a few times after greasing. This works the grease around the full circumference of the pin and pushes out trapped contaminants.
- Wipe the excess — extruded grease attracts dirt that turns into lapping compound.
On polyurethane suspension bushings (common in automotive and light truck applications), never use petroleum-based grease—it breaks down urethane and causes premature failure. Penrite’s Pin & Bush Grease or a silicone-based grease with PTFE are the safe alternatives here.
Choosing Between Moly and Non-Moly Greases
Molybdenum disulfide is the default solid lubricant for heavily loaded pins because it withstands pressures where oil films rupture. For bronze or brass bushings running at low speed under heavy loads, a moly-fortified NLGI #2 EP grease is still the right call. In wet environments, switch to a water-resistant calcium-based EP grease if available, though lithium-based moly greases already offer good water resistance for most construction conditions.
Three common mistakes kill pin life faster than lack of maintenance: using general-purpose grease without EP additives on a 50-ton loader; not cycling the joint after greasing (which leaves half the bearing surface dry); and treating all bushing materials the same—petroleum grease on polyurethane bushings fails within weeks. Match the grease to the bushing material, not just the machine.
FAQs
What happens if I use chassis grease on bucket pins?
Standard chassis grease lacks extreme-pressure additives and gets squeezed out under heavy loads, leaving metal-on-metal contact that accelerates wear on the pin and bushing. You’ll see galling and grooving within hours of heavy use.
Can I mix different brands of pin grease?
Mixing different thickener types (lithium, clay, calcium) can cause the grease to soften or harden unpredictably and reduce its load capacity. Stick with one formulation per machine until the old grease is fully purged.
How often should I grease pins and bushings on a loader?
In dusty conditions, increase frequency—contaminated grease wears out joints faster than no grease at all.
References & Sources
- Penrite Oil. “Pin & Bush Grease.” Product specifications for clay-based grease safe for polyurethane bushings.
- UNIVERZAL. “Pin & Bushing Grease.” Published technical data including NLGI grade, dropping point, and Timken OK load.
- CGN Lubricants. “Pin and Bush Grease.” Specifications for lithium-based grease with graphite and molybdenum disulphide.