Greasing is the cheapest maintenance job on an excavator and the one most often done badly. A tube of grease costs a few dollars and ten minutes of an operator's morning, yet skipped or sloppy greasing is behind a large share of premature pin and bushing wear, sloppy buckets, and expensive front-end rebuilds. If your excavator's arm feels loose, squeaks under load, or shows shiny metal at the joints, the grease schedule is usually the first place to look.
This guide explains how to grease an excavator properly: every grease point on a typical machine, how often each one needs attention, which grease to use, how much to apply, and the mistakes that quietly destroy pins and bushings. Follow it alongside your machine's manual, because exact point counts and intervals vary by model — but the technique below works on virtually every crawler and wheeled excavator in service today.
Quick Answer: How Do You Grease an Excavator Properly?Grease every pin on the front equipment daily — every 8 to 10 operating hours — pump slowly until clean grease appears evenly around the joint, then stop. Over-greasing blows out seals, under-greasing wears pins out, and both mistakes cost far more than the ten minutes the job takes.
Walk the machine in the same order every time, count your fittings against the manual, and use a lithium-complex EP grease unless your manual specifies otherwise. The sections below give you every grease point, the intervals, and the mistakes that ruin pins and bushings.
Grease does three jobs at once. It separates the pin from the bushing so steel never rubs directly on steel, it carries away fine dirt and wear particles when fresh grease pushes old grease out of the joint, and it seals the joint against water, dust, and mud. When any of those jobs fails — because the grease ran out, washed out, or was never pumped in at all — wear accelerates fast. A pin that should last thousands of hours can develop noticeable play in a few hundred hours of dry running, and once play starts, it only gets worse. That is why greasing belongs in the same daily routine as the walk-around inspection covered in our pre-start guide, not in the "when I remember" category.
1. All the Grease Points on a Typical Excavator
A standard 20-ton class excavator has roughly 15 to 25 grease points, depending on the attachment and whether the machine has a blade or a swing bearing with its own fittings. Mini excavators have fewer; larger machines and machines with quick couplers or thumbs have more. Walk the machine in the same order every time so no point is ever missed.
Front work equipment: boom, arm, and bucket
Start at the front, where the loads are highest and the wear shows first:
- Boom foot pins (2): where the boom mounts to the upper structure. These carry the full weight of the front equipment.
- Boom cylinder pins (4): rod end and base end of each boom cylinder.
- Arm-to-boom pin (1) and arm cylinder pins (2): the elbow joint of the machine.
- Bucket cylinder pins (2): rod and base ends of the bucket cylinder.
- Bucket linkage pins (4–6): the H-link and connecting links between the arm, bucket cylinder, and bucket. These are the most commonly missed points because they are tucked behind the linkage.
- Bucket pins (2): where the bucket itself pivots on the arm.
- Quick coupler pins (2–4, if fitted): grease the coupler body and its locking pins exactly as the coupler manual directs.
Work from the cab outward or from the bucket inward — either order works, as long as it is the same order every day. Count the fittings as you go and compare the count with your manual. If the count comes up short, you have missed one, and it is almost always a linkage pin hiding behind a plate.
Swing bearing, swing gear, and undercarriage
The swing system is easy to forget because it is under your feet rather than in front of your eyes. Most machines have:
- Swing bearing grease points (2–4): usually accessed from the top of the upper structure near the cab. Grease these slowly while an assistant slowly rotates the upper structure, so the grease distributes around the whole bearing race instead of pooling in one spot.
- Swing gear / pinion: many machines grease the swing gear through the same circuit or a separate fitting; check the manual, because a dry swing gear grinds itself to dust quietly.
- Track adjuster and idler fittings: not daily grease points, but check them during the weekly service. Track tension is set with grease pressure, so a leaking adjuster seal shows up as a track that will not hold tension — a topic covered in our guide to excavator undercarriage maintenance.
- Blade pins and cylinders (if fitted): mini excavators with a dozer blade have two to four extra points at the blade arms and lift cylinder.
2. How Often Should You Grease an Excavator?
The honest answer is: more often than most operators do. Manufacturers' standard guidance for the front work equipment is daily — every 8 to 10 operating hours — and that interval shortens in harsh conditions. Use this table as a starting point, then adjust to your manual and your working environment.
| Grease point group | Normal interval | Harsh conditions* |
|---|---|---|
| Boom, arm, bucket, and linkage pins | Every 8–10 hours (daily) | Every 4–8 hours |
| Swing bearing | Every 50–100 hours, rotating slowly | Every 50 hours |
| Swing gear / pinion | Per manual (often 100 hours) | Per manual, check monthly |
| Quick coupler and thumb pins | Daily, with the front equipment | Daily |
| Blade pins (mini excavators) | Daily | Daily |
*Harsh conditions include wet or muddy ground, dusty demolition or quarry work, underwater or dredging work, very hot weather, and continuous high-load digging such as rock breaking. In these conditions, water and grit wash grease out of the joints faster, so the daily interval is a minimum, not a target.
A practical rule used by many fleet managers: grease at the start of every shift, before the machine gets hot and dirty, and grease again at midday on long shifts in mud or dust. It takes ten minutes, and it is far cheaper than a pin and bushing kit. Record the service on the daily inspection sheet so a missed day is visible, not guessed.
3. Which Grease Should You Use?
Not all grease is equal, and the wrong type can be worse than a short interval. For most excavator pins and bushings, the standard recommendation is a lithium-complex extreme-pressure (EP) grease, NLGI grade 2, with molybdenum disulfide (moly) content of around 3 to 5 percent for heavily loaded pivot pins. Moly grease clings to the metal and keeps protecting under the shock loads that digging produces.
Three rules matter more than brand loyalty:
- Match the manual first. Some manufacturers specify a particular grease type or forbid moly grease in certain bearings (notably some swing bearings). The manual wins over any general guide, including this one.
- Do not mix grease types casually. Lithium, calcium, and polyurea greases use different thickeners, and mixing incompatible types can soften the grease until it runs out of the joint. If you must switch types, purge the old grease fully by pumping until only the new grease emerges, and note the change on the machine's service record.
- Use fresh, clean grease. A tube left open in the cab collects dust, and dust pumped into a pin joint is abrasive paste. Keep tubes capped, wipe the fitting before you attach the gun, and never grease through a fitting caked in mud — clean it first or you will pump the mud straight into the bushing.
4. How to Grease an Excavator, Step by Step
Good technique matters as much as the schedule. Pumping blindly until grease squirts everywhere wastes grease, makes a mess, and can blow out seals. Do it this way instead:
1. Park safely and position the equipment
Park on level ground, lower the bucket flat to the ground, shut the engine off, and engage the lock lever before you climb around the machine. For the front pins, resting the attachment on the ground takes the load off the joints and lets grease flow evenly around the pin. Greasing a joint under full load forces grease to one side only.
2. Clean every fitting before you attach the gun
Wipe each grease nipple (zerk fitting) with a rag. If a fitting is damaged, bent, or clogged, replace it — a five-minute fitting change beats a seized pin. A fitting that will not take grease at all usually has hardened old grease behind it; try working the joint back and forth gently, or replace the fitting and try again before assuming the pin is blocked.
3. Pump slowly until fresh grease appears — then stop
Attach the grease gun firmly so it does not pop off under pressure, then pump slowly and steadily. Watch the joint: fresh grease should begin to emerge evenly around the pin seals or from the relief side of the bushing. As soon as you see clean, new grease all the way around, stop. Two or three extra pumps after that point only blow out seals and waste grease. For swing bearings, pump slowly while the upper structure rotates a full turn so the grease spreads around the race.
4. Wipe off the excess and check for problems while you are there
Wipe the purged old grease away so the joint stays clean and the next service can see what is happening. While you are at each pin, look for the warning signs: play or movement in the joint, cracked or missing seals, a pin drifting sideways, shiny metal dust, or grease that comes out grey and gritty instead of clean. Any of these means the joint needs attention beyond routine greasing — log it and tell the shop before it becomes a rebuild.
5. Choose the right grease gun for the job
A manual lever gun is fine for one machine and gives the best feel for when a joint is full. A battery-powered grease gun is faster on a fleet and keeps pressure steady, but it also makes it easy to over-grease and blow seals if you hold the trigger too long — count your pumps, or use a metered gun. Pneumatic guns belong in the shop, not bouncing around in a cab. Whichever gun you use, keep a spare tube on the machine; a gun that runs dry halfway around the machine is how points get skipped.
5. Mistakes That Ruin Pins and Bushings
- Greasing on a calendar instead of on hours. "Once a week" means nothing if the machine ran 60 hours that week. Track operating hours, not days.
- Skipping the hidden linkage pins. The bucket linkage set is the most skipped and the most expensive to rebuild. Count your fittings every time.
- Over-greasing. Pumping until grease is everywhere blows dust seals, and a blown seal lets grit in. Stop when fresh grease shows all the way around the joint.
- Greasing a dirty fitting. Mud on the nipple goes straight into the bushing. Wipe first, every time, even when you are in a hurry.
- Mixing incompatible greases. Different thickener types can liquefy each other. Stick to one approved type per machine.
- Greasing only when the machine squeaks. By the time a pin squeaks, metal is already wearing metal. Squeaking is a failure alarm, not a service reminder.
- Ignoring the swing bearing. It turns slowly and silently, so it gets forgotten — until the slew feels rough or the bearing develops play, at which point the repair bill dwarfs a year's worth of grease.
Each of these mistakes is cheap to avoid and expensive to fix. A full pin and bushing rebuild on a 20-ton machine can run into thousands of dollars in parts and days of downtime, while the grease that would have prevented it costs less than a tank of diesel over a whole year.
6. Signs Your Excavator Needs Greasing — or Already Needs Repair
Learn to tell routine service from real damage. Normal signs that greasing is due include slightly stiff movement first thing in the morning and old, dark grease purging from the joints. Warning signs that something is already wrong include visible play when you rock the bucket by hand, clunking under load, a pin that has shifted sideways out of its boss, grease leaking from a cracked seal, or a joint that will not take grease at all. The first group is solved with the grease gun. The second group needs a mechanic, and running the machine hard in the meantime only enlarges the repair. If you are also chasing lost digging power, check our guide to why an excavator loses hydraulic power — but rule out dry pins first, because a seized linkage feels surprisingly like a hydraulic problem.
7. Building a Greasing Routine That Actually Sticks
The best greasing schedule is the one that survives a busy week. Put the grease gun and a rag in the same place on every machine, print the point count on the daily inspection sheet, and make greasing the first job of the shift, before the first bucket of dirt moves. Owners with several machines should standardize one grease type across the fleet where the manuals allow it, so there is no wrong tube to grab. And when a machine changes hands — a new operator, a rental return, a second-hand purchase — grease every point fully on day one and inspect every joint, because you are inheriting the previous operator's habits, good or bad.
For more on keeping the whole machine in shape, see our excavator maintenance checklist and our walk-around inspection guide. Greasing is one chapter of that routine, but it is the chapter that most directly decides how long your pins, bushings, and front equipment last.
Greasing properly is unglamorous work, and that is exactly why it gets skipped. But ten careful minutes at the start of every shift is the single best return on investment in excavator ownership: quiet joints, tight pins, precise digging, and a front end that lasts the life of the machine instead of wearing out halfway through it. Make it a habit, count your points, and let the grease do its job.
