Oil light is basically a oil pressure gauge, that only reads (turns on) when there is no pressure. Usually by the time it comes on and is noticed, damage may already be happening.
Your vehicle may hold five to six quarts of oil. The dipstick checks "volume". The dipstick may only read the top "two" quarts, if it is down two and a bit, It will not show on the stick. However, you still have three to four quarts below that still able to lubricate and the oil pump can still produce pressure.
The big thing here is to keep it at the proper level on the stick.
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Monday, May 1st, 2017 AT 6:39 PM