Engine Oil type

Asked by Apr 26, 2017 at 03:18 AM

Question type: Maintenance & Repair

I recently had my vehicle serviced and used castrol engine oil 5W30.
Previous service titan 15W40 oil was used. I dont have any issues with my
car but someone tells me 5W30 oil is not good for my diesel engine. Please
advise if there is any need for me to worry.
My vehicle is an Isuzu KB300LX Dteq 5th gen.

Thanking you in advance.

3 Answers


Call an auto parts store, they will look up what type of oil goes into that engine. Or look in the owners manual. Some times the weight oil is marked on the oil filler cap also.


5W30 is generally not a diesel approved engine oil. I would go back and have them put the correct engine oil in your rig. The few diesels I have owned all ran diesel approved 15W40. Better make sure they put the right oil filter on there too, some have an antidrain back valve that is very important to diesels.

If I accidentally added 1.5 quarts of 5-30 to a diesel that has 15-40, will it be ok until next service?

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