Kubota D1503-M-E3 Operator's Manual page 23

A Oil used in the engine should have API classification and Proper SAE Engine Oil according to the ambient
temperatures as shown below:
Above 25 (77 ) SAE30, SAE10W-30 or 15W-40
0 to 25 (32 to 77 ) SAE20, SAE10W-30 or 15W-40
Below 0 (32 ) SAE10W, SAE10W-30 or 15W-40
A Recommended API classification
Refer to the following table for the suitable American Petroleum Institute (API) classification of engine oil according to
the engine type (with internal EGR, external EGR or non-EGR) and the Fuel Type Used : (Low Sulfur, Ultra Low Sulfur
or High Sulfur Fuels).
Fuel type
High Sulfur Fuel CF
[0.05 % (500 ppm) (If the "CF-4, CG-4, CH-4 or CI-4" engine oil is used
Sulfur Content < with a high-sulfur fuel, change the engine oil at shorter
0.50 % (5000 ppm)] intervals. (approximately half))
Low Sulfur Fuel
[Sulfur Content <
0.05 % (500 ppm)] or
CF, CF-4, CG-4, CH-4 or CI-4
Ultra Low Sulfur Fuel
[Sulfur Content <
0.0015 % (15 ppm)]
EGR: Exhaust Gas Re-circulation
Engine oil classification (API classification)
Engines with non-EGR
Engines with internal EGR
MAINTENANCE
Engines with external EGR
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CF or CI-4
(Class CF-4, CG-4 and CH-4 engine, oils
cannot be used on EGR type engines.)
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