Quick answer:<\/strong> Most crane gearboxes use EP industrial gear oil in ISO VG 220 or 320 viscosity. The gearbox nameplate has the final word. Match the grade, never mix oil types, and change the oil after the running-in period, then by condition.<\/p><\/blockquote>\nNeed to pick the right crane gearbox oil type for your unit? The wrong oil films thin under load, cooks the seals, and scores the gear teeth. The right oil is one decision away: read the nameplate, match the viscosity, and follow the change rules below.<\/p>\n
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Why the Right Oil Type Matters<\/h2>\n
A crane gearbox runs under shock loads that ordinary oil cannot survive. Inside your gearbox, the oil does four jobs:<\/p>\n
\n- It carries load.<\/strong> Extreme pressure (EP) additives form a film on the gear teeth that stops metal-to-metal scoring.<\/li>\n
- It moves heat.<\/strong> Oil pulls friction heat away from the mesh and the bearings.<\/li>\n
- It seals out contaminants.<\/strong> The oil film keeps dust and moisture away from the gear surfaces.<\/li>\n
- It protects at start-up.<\/strong> The right viscosity flows fast on cold mornings, when most wear happens.<\/li>\n<\/ul>\n
Choose the wrong type or grade, and the result is always the same: worn teeth, leaking seals, and a gearbox that fails long before its design life.<\/p>\n
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The Three Oil Types You Will Meet<\/h2>\nMineral EP gear oil<\/h3>\n
Standard closed gearboxes \u2014 most crane travel and hoist units \u2014 run on mineral-based EP gear oil, often marked CLP. It handles shock loads at the lowest cost. This is the default fill for most crane duty.<\/p>\n
Synthetic gear oil<\/h3>\n
Synthetic oils hold their viscosity better at both temperature extremes and last longer between changes. Hot climates, cold sites, and high-duty gearboxes benefit most. You can run synthetic from new, but check your manual first: seals and ratings are designed around the specified oil.<\/p>\n
Worm gear oil<\/h3>\n
Worm gearboxes are different machines. The sliding mesh between the worm and the wheel needs special oils with friction modifiers, not standard EP gear oil. Filling a worm unit with EP oil can actually increase wear. If your gearbox is a worm type, the oil spec on the plate is not optional.<\/p>\n
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Viscosity Grades: What ISO VG Means<\/h2>\n
ISO VG numbers describe oil thickness. A higher number means thicker oil. The grade decides how well the oil stays on the teeth at your working temperature.<\/p>\n
\n\n\n| Factor<\/th>\n | Where the value comes from<\/th>\n | Typical picture<\/th>\n<\/tr>\n<\/thead>\n |
\n\n| Viscosity grade<\/td>\n | Gearbox nameplate or manual<\/td>\n | ISO VG 220 and VG 320 cover most crane gearboxes<\/td>\n<\/tr>\n |
\n| Oil specification<\/td>\n | Manual<\/td>\n | EP industrial gear oil (CLP); worm units need worm gear oil<\/td>\n<\/tr>\n |
\n| Oil quantity<\/td>\n | Level plug, dipstick, or manual<\/td>\n | Fill to the level mark \u2014 never to the top<\/td>\n<\/tr>\n |
\n| Site condition<\/td>\n | Ambient temperature range<\/td>\n | Cold sites often need a lower grade than warm ports<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Two warnings about this table. First, VG 220 and VG 320 are common grades, not your grade \u2014 the nameplate wins every time. Second, if your crane works across a wide temperature range, tell your supplier the site conditions, because the correct grade may change with them.<\/p>\n <\/p>\n How to Choose the Correct Oil<\/h2>\nWork through this order and you cannot go wrong:<\/p>\n \n- Read the nameplate.<\/strong> It states the oil type and viscosity grade the gearbox was designed around.<\/li>\n
- Match the full specification.<\/strong> The manual lists the required EP level and ISO grade. Match the spec, not just a brand name.<\/li>\n
- Adjust for the site.<\/strong> Extreme cold or heat shifts the right grade. Your gearbox maker can confirm the alternative.<\/li>\n
- Fill to the level mark.<\/strong> Overfilling whips the oil into foam and overheats the unit.<\/li>\n
- Log the fill.<\/strong> Record the type, grade, quantity, and date on the gearbox or in your maintenance file.<\/li>\n<\/ol>\n
<\/p>\n When to Change Crane Gearbox Oil<\/h2>\nChange intervals are not universal. They depend on duty class, load, temperature, and the oil itself. Use this sequence:<\/p>\n \n- First change: after the running-in period.<\/strong> New gears shed wear particles. Your manual defines this first interval, and it is shorter than any later one. Respect it.<\/li>\n
- After that: follow the manual, then the condition.<\/strong> Check the level and look at the oil regularly. Dark color, a milky look from water, or metal glitter means change now, whatever the calendar says.<\/li>\n
- After water ingress or overheating: change immediately.<\/strong> Contaminated oil keeps damaging gears until you drain it.<\/li>\n<\/ul>\n
Condition beats calendar every time. A monthly two-minute oil check protects your gearbox better than a fixed schedule nobody inspects.<\/p>\n <\/p>\n Gearbox Oil Mistakes That Cost You<\/h2>\n |
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