Do I refill engine oil based on what I drained or the manual?
Manufacturers specify capacity for a completely dry engine, which is always more than what actually drains out during a standard oil change due to residual fluid trapped in internal galleries. Pouring in the full manual amount based on a partial drain will overfill the crankcase, whereas trusting the dipstick ensures you hit the correct operational level safely.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from September 2026.
- It is not one crowd: 5 people on Reddit and 1 on Stack Exchange ran into the same thing.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Filling based on the amount drained rather than the manual specificationDid this help you?
- 2Checking the dipstick and adding oil until it reaches the full lineDid this help you?
- 3Checking the dipstick and adding more oil based on forum advice.Did this help you?
- 4watching multiple YouTube videos to pick the best methodDid this help you?
- 5measuring the exact amount of fluid removed from the panDid this help you?
- 6Testing the final coolant mixture with a refractometer instead of relying purely on mathematical calculationsDid this help you?
- 7Doing a standard drain and fill instead of a full flush when there are no underlying system issuesDid this help you?
- 8Checking the dipstick multiple times after wiping itDid this help you?
- 9Posting photos of the dipstick online for feedbackDid this help you?
- 10Asking forum members for confirmation on engine sounds and oil levelsDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I drained 4 qts of old oil. Now the owner's manual says to put in 4.5 qts of new oil, but since I drained only 4 qts I only topped up 4 qts of new oil since my thinking is that some residual old oil is probably still in the oil galleries etc.”source ↗
“Did I do it right? Or it doesn't matter if 4 qts got drained,do I still need to fill in 4.5 qts of new oil? I don't wanna over fill it.”source ↗
“Is my engine oil level good enough. I did the oil change 3 weeks ago. Filled about 5 litres of oil. Noticeable traces of oil are there up to the first dot. And there’s small traces of oil between the first and second dot”source ↗
“Some videos mention measuring how much fluid is removed and others say to fill until fluid comes out of the drain plug with the plastic insert in; it's the plastic cylinder in the pan that allegedly is where the fill line is.”source ↗
“One said to empty.. and then fill until it starts dripping over the that plastic cylinder.. possibly putting the plug back in and warm the car up and take the plug back out after the fluid has expanded.”source ↗
“Any thoughts? I'd prefer doing this myself.”source ↗
“If I drain and flush it with distilled water, should I assume there is 0.66 gal of water left in there (2.01-1.35)? So then I can use concentrated antifreeze 1 gal and add 0.35 gal of water to end up at 50/50?”source ↗
“This is only my first time doing an oil change by myself so I just wanted to come here and make sure”source ↗
“oil is on first line of the stick but not sure how much to add? my first time.”source ↗
Where this came up
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