On most construction sites the excavator sets the pace, and its pins and bushes are where it wears first. Bucket and linkage pins move slowly, back and forth, under shock loads, in dust and mud. Once the grease film is gone, steel rubs on steel and a bush can wear oval in a few weeks. The fix costs very little: the right grease, at the right interval, in the right amount.
Grease the bucket pins and bucket linkage every 10 operating hours (once a shift), and more often when digging in water or mud. Grease the boom and arm pins at the interval in the operator's manual, commonly every 50–100 hours and daily on heavy work, and the slew ring at its own, longer interval while turning the upper structure. Use an EP grease of NLGI 2, with molybdenum disulphide (MoS₂) on heavily loaded pins where the maker allows it.
Every manual is a little different, so treat these as typical values and follow the maker's chart for your model.
| Grease point | Typical interval (check the manual) | Grease |
|---|---|---|
| Bucket pins and bucket linkage | Every 10 hours or once a shift; more often in water, mud or heavy dust | EP grease NLGI 2, MoS₂ where allowed |
| Arm (stick) and boom pins, cylinder ends | Commonly every 50–100 hours; daily on heavy duty | EP grease NLGI 2, MoS₂ where allowed |
| Slew ring (swing bearing) | Commonly every 250–500 hours | Lithium complex NLGI 2 or as specified |
| Swing pinion and ring gear | Check the grease bath at service; replace as specified | The maker's specified gear grease |
| Backhoe loader front and rear linkages | Daily | EP grease NLGI 2 |
| Crane wire ropes (on cranes and attachments) | When the rope looks dry | Wire rope lubricant |
Excavator pins work in the worst conditions for a grease film: slow, oscillating movement that never builds a full oil wedge, plus shock every time the bucket hits rock. Two things help:
NLGI 2 is the right consistency for grease guns and central lubrication systems in Indian conditions. A firmer NLGI 3 is harder to pump in long lines. Our guide to NLGI grease grades explains the numbers, and EP2 vs MP3 grease covers why "MP3" is not a substitute for an EP grease on pins.
For slew rings, use the grease the maker names. Many specify a lithium or lithium complex EP grease without MoS₂ for the raceway.
For pins and bushes the rule is simple: pump until fresh grease appears at both ends of the pin and the old, dirty grease has been pushed out. That purge is what clears dust from the joint.
For the slew ring, grease while slowly turning the upper structure, for example in steps of about 90°, so the grease spreads around the whole bearing. Do not force grease until the seals lift; a little fresh grease at the seal lip is enough.
If a nipple refuses to take grease, do not skip it. A blocked nipple or a seized grease channel means that pin is running dry. Replace the nipple or clear the channel the same day.
The grease fitting on the track adjuster is used to set track tension, not to lubricate. The grease inside is under very high pressure. Adjust it only as the manual describes and never loosen the relief valve quickly or stand in front of it.
Most excavator pin wear starts with dust pushed in by the grease gun, not with a lack of grease.
Excavator hydraulics run hot in an Indian summer and pull in dirt every time a cylinder rod retracts. Three habits prevent most hydraulic failures:
Any one of these means the pin needs grease today, and the schedule needs a look.
For the full list of oils and greases a construction fleet needs, see our page on construction equipment lubricants.
How often should excavator bucket pins be greased?Typically every 10 operating hours, which means once a shift, and more often when working in water, mud or heavy dust. Always check the operator's manual for your model.
Which grease is best for excavator pins and bushes?An EP grease of NLGI 2. One with molybdenum disulphide (MoS₂) protects slow, heavily loaded, shock-loaded pins when the oil film is squeezed out, where the maker allows it.
How do I grease an excavator slew ring?At the interval in the manual, while turning the upper structure in steps so the grease spreads around the bearing. Use the grease the maker specifies and do not force it until the seals lift.
Is the grease nipple on the track adjuster a lubrication point?No. The grease in the track adjuster sets track tension and is under very high pressure. Adjust it only as the manual describes and never loosen the valve quickly.
Running excavators, loaders or cranes? Send us the machine models and your current grease, and our team will suggest the right grease and a site greasing schedule.