How often should you change the oil in a gear unit?

The frequency of oil changes in a gear unit depends on the specific model and operating conditions, so the starting point should always be the manufacturer's Operating and Maintenance Documentation (DTR). Oil change intervals are described in the manufacturer's manuals (e.g. for NORD drives in manual B1000).

NORD B1000 manual – Geared motors and gear units Original manufacturer documentation, edition pl-2424 · PDF, 3.9 MB, 80 pages Download the manual

What does the oil change interval for a gear unit depend on?

The key factors are usually:

• load and operating time (continuous/intermittent),
• operating temperature and ambient conditions,
• installation position and sealing (e.g. risk of leaks),
• the type of lubricant used, in accordance with the designation on the name plate.

Where can you check the recommended interval for a specific gear unit?

You will find the recommendations in the manufacturer's DTR. For NORD solutions, the right point of reference is the "Geared motors and gear units – B1000" manual (PDF), also available in other languages on the manufacturer's website. If in doubt, contact us!

Why is it worth changing the oil at the right intervals?

It is worth keeping to the correct intervals because the oil in a gear unit does not last "forever" — over time it loses its properties and accumulates contaminants, which directly affects the service life of the gear unit.

Regular oil changes mean:

• Less wear and fewer failures: fresh oil maintains a stable lubricating film, reducing friction, noise and micro-damage to gear wheels and bearings. Old oil (containing swarf, water, oxidised) accelerates wear.
• Lower temperature and better efficiency: the correct viscosity and anti-wear additives improve cooling and reduce energy losses; "tired" oil more often causes overheating and a drop in efficiency.

• Reduced risk of corrosion (especially with moisture/condensation),
• Protection of the shaft seal (old oil can be more aggressive due to oxidation products),
• It allows problems to be spotted earlier (e.g. an unusual amount of swarf when draining),
• It genuinely reduces downtime and repair costs, because a gear unit failure is usually far more expensive than the oil service itself.

What if I don't have the DTR or don't know which interval to adopt?

In that case, it is best to rely on the data from the name plate and the application conditions, and to seek advice on choosing the interval. SPEC SERWIS provides advisory support in selecting solutions and in liaising with NORD – so that a sensible service schedule can be adopted without "guessing" at dates.