Generator Oil Type & Capacity Finder
Do not choose generator oil from a generic "most generators use 10W-30" rule. The correct viscosity and capacity can change by brand, model and even closely related variants. Use the finder below for an exact model match from manufacturer documentation. If your model is not in the database, use its owner manual rather than borrowing a specification from a similar generator.
Find your generator oil type and capacity
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Data last updated: 2026-09-01
Every field on a result card is a column from the manufacturer's own document for that exact model, with the source linked. The finder returns one explicit row or nothing: it does not infer a specification from engine size, wattage, a similar model number or another model from the same brand.
Why the exact model matters
Two generators from the same brand can require different oil. Champion, for example, publishes 5W-30 for model 201046 while model 201183 is listed with 10W-30. Honda's current EU2200i manual recommends SAE 10W-30 for general use and gives a maximum oil capacity of 14 fl oz (0.44 L), while the EU3000is manual lists 0.58 US qt (0.55 L).
That is why this page is a lookup rather than a universal oil recommendation.
Verified examples from the current database
| Generator | Published oil guidance | Published capacity |
|---|---|---|
| Honda EU2200i | SAE 10W-30, API SJ or later, for general use | 14 fl oz (0.44 L) maximum |
| Honda EU3000is | SAE 10W-30, API SJ or later, for general use | 0.58 US qt (0.55 L) |
| Champion 201320 | 10W-30 for typical use; manual provides a temperature chart | 18.6 fl oz (550 ml) |
| Predator 59137 | SAE 10W-30 for general use | 20 fl oz |
| Westinghouse WGen9500DF | SAE 10W-30 | 1.16 qt (1.1 L) |
| Westinghouse WGen11500TFc | SAE 10W-30 | 1.26 qt (1.2 L) |
| Cummins Onan QG 4000 / 3600 LP, KY P-R | Viscosity depends on ambient temperature | 1.6 qt (1.5 L) |
10W-30 is common, but it is not a universal answer
Several models in the database do specify 10W-30, but that does not make it safe to apply 10W-30 to every generator. One current Champion 2500W inverter, model 201046, is published with 5W-30. Cummins gives multiple viscosity grades for the QG 4000/3600 LP KY P-R depending on expected ambient temperature. Those differences are exactly why a model-level source matters, and why this page asks for the model before it answers.
Capacity is just as model-specific as viscosity
Oil capacity is not a proxy for generator wattage. Even within the same broad category, published capacities vary substantially. Filling from a generic internet chart can overfill or underfill the crankcase.
Use the capacity in the exact manufacturer source, keep the generator level when the manual requires it, and use the manual's oil-level method rather than assuming the listed capacity is always the amount needed after every drain.
Temperature changes the answer on some models
Where a manufacturer publishes a viscosity chart or explicit temperature ranges, the finder shows that guidance. Cummins, for example, gives separate viscosity ranges for the QG 4000/3600 LP KY P-R. Honda and Champion also publish temperature-based viscosity charts in their manuals.
If the result points at a manufacturer chart, open the source instead of extrapolating the range from another brand.
Oil-change intervals also vary
The first oil change can be much earlier than the regular interval. Honda specifies a first change at 20 hours on the EU2200i. Champion model 201320 specifies an oil change after the first 5 hours, then every 100 hours or annually under normal service, with more frequent changes under heavy load or high temperatures.
The finder only displays an interval when the source for that exact row supports it.
Have a Generac?
GridComfort already has a dedicated Generac Generator Oil Type & Capacity guide covering standby and portable Generac guidance. Keeping that intent on its existing URL avoids splitting the Generac cluster across two pages, so Generac models are not duplicated into the database behind this finder.
What this database does not do
This finder does not guess from a similar model number, turn a generic engine-size chart into a model specification, treat a retailer listing as a manufacturer specification, or claim that one oil brand is required unless the manufacturer says so. It does not replace the owner manual for a model that is not yet in the database.
The database grows only when a new row has a manufacturer source and the exact model or spec number is identifiable.
If the oil specification in your manual conflicts with a sticker, service bulletin or updated manufacturer document for your exact generator, use the latest manufacturer guidance or contact the manufacturer. Stop using a generator that is leaking oil, repeatedly triggering low-oil shutdown after the level is corrected, or showing signs of internal engine damage.
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