OCI- oil consumption

[Bullwinkle007]

I own a 2012 Honda Accord 2.4L. 248k miles One thing I've noticed, and running either M1 euro 5/40 or Castrol euro 5/40 it's entire life, at 5k miles, it's 1k qt low, at 3k miles, it's full. So somewhere between the 3k and 5k it uses 1qt. I change it at 5k miles. I feel this is the point where the add packs to the oil is starting to break down. I change the oil now at the 5k mark.

I did long haul trucking from 1999-2002. The company I was working for did 30k oci. At 10k miles on the oil, it was down a gal every 5k after. Of course lots of idle time and hwy miles.

Seems to me, once you reach that miles on a good engine, if the oil is down regardless of what the lab says in regards to the TBN, that should be your OCI time. Oil and a filter is cheap if dyi

 

[Lubener]

I believe more of the facts given with a UOA than your theory.

 

[himemsys]

Keep in mind the oil sump shape makes a difference on perceived oil level. If the sump tapers down, then the same amount of oil loss will appear as more loss on the dipstick. It could be that you are losing a constant amount of oil throughout the OCI, but it appears to consume faster as you get further into the OCI because the sump is narrowing in volume as the consumption occurs.

If you really want to know, then the next time you change your oil, underfill it, then slowly add oil while checking where it ends up on the dipstick. You can then tell how much oil is in the car at the low mark, how much it takes to get from low to 1/4, 1/2, 3/4, and to the full mark. This will show you how the sump shape affects the oil level. It could be that it only takes 3/8qt to get from low to middle, but it takes 5/8qt to get from middle to full.

 

[doublebase]

Keep in mind the oil sump shape makes a difference on perceived oil level. If the sump tapers down, then the same amount of oil loss will appear as more loss on the dipstick. It could be that you are losing a constant amount of oil throughout the OCI, but it appears to consume faster as you get further into the OCI because the sump is narrowing in volume as the consumption occurs.

If you really want to know, then the next time you change your oil, underfill it, then slowly add oil while checking where it ends up on the dipstick. You can then tell how much oil is in the car at the low mark, how much it takes to get from low to 1/4, 1/2, 3/4, and to the full mark. This will show you how the sump shape affects the oil level. It could be that it only takes 3/8qt to get from low to middle, but it takes 5/8qt to get from middle to full.

Never thought of it this way. Interesting.

 

[doublebase]

I owned a Lexus LS 460 once, and for the longest time I’d change it at 5,000 mile intervals. Decided to push it to the 7,500-8,000 mark and what I noticed is that after 5,000 it would start to use oil, seemed like nothing up until that point, but after 5,000 it would start to drink oil...2 quarts between 5,000 to 7,500.

I never considered the theory posted by himemsys though.

 

[BigCahuna]

I don't think it's so much mileage of the engine hat causes consumption, as the oil thinning out and being consumed. I'm a believer in using a heavier grade of oil, to curb consumption. My wife's chevy equinox was using a qt every 750 miles, of the 5/30 the mfgr called for. I tried 10/30 and that helped minimally. Then I went up to 10/40 and that helped alot. I even used a 50/50 mix if 10/40 and 20/50, for the summer and that worked big time. No mind you this car only had 35k miles on it when we got it from my sister ,who bought it new. I know how it was used and it was dealer maintained, if that means anything. After 50 years of driving and maintaining all types of vehicles, the only thing that made any difference in oil consumption was a heavier grade of oil. All those gimmick fluids only wasted money that would have been better spent on heavier oil. My 2 devalued cents.,,,

 

[himemsys]

Never thought of it this way. Interesting.

I hadn't either til recently. Another thing to consider is the amount of oil it takes to go from the low mark to the full mark is not always 1 qt. I think that is a generalization that is fairly accurate, but it depends on the car manufacturer and the sump capacity too. My '03 Civic takes about .75 qt to get to full from low and our '06 Infiniti takes about 2 qts to go from low to full. I have not checked our CRV yet, but with a 3.7 qt fill, I'm guessing it's between .75 and 1 qt. I wonder if a more accurate generalization would be 25% of the fill capacity. That seems to work out mathwise for my small sample size. So a 4qt fill would be about 1qt between low and full.

 

[circuitsmith]

If you check and top off the oil frequently the taper of the oil pan and the span of the dipstick marks won't matter for measuring consumption rate.
It's been long observed that oil consumption rate sometimes increases as the oil ages.
I think molecules are weakened with mileage, then shearing in the ring cylinder area and immediately burned, so remaining oil viscosity isn't reduced.

 

[blupupher]

My kids Scion xB is similar.
Dipstick reads full at 3,000 miles, when I change the oil @ 5,000 miles, it is down 1/2 to 1 qt.

I do use 0w-20 oil in it, so that may be part of it. Will be switching to 5w-30 soon (almost done with my Xw-20 stash).

 

[frisco]

My 05 CRV with k24 does that with supertech 5w20.

Last 4 changes was 8k kms interval. 2 times with ST 5w20, 2 times with Pennzoil platinum 5w20.

The ST would always read 3/4 on the dipstick before change it. The Pennzoil is always on the full mark.

 

[SammyChevelleTypeS3]

Try a different oil brand...?
I been really lucky and only had a few oil users way back in the early to mid 70s.
Some folks including me have experienced 1/2 to 1 qt use in between 3000 to 5000
mile oci when using one certain oil brand. But no loss with other brands. This certain
oil is in all the stores and quite popular since the early automobile days.....? No mechanic
could explain it to me but they knew what I was talking about from their own experiences.

 

[Graham Piccinini]

My 2 devalued cents.,,,

Fun-useless-fact O'Clock, about the $0.02.
- This idiom has been used since the late 1800s. It comes from the much 15th-century British use of twopence or tuppence to mean 'of little or no value; unimportant' which gave rise to the idioms for two cents and like two cents.
- CPI Inflation Calculator only goes back to 1635, so I couldn't check back far enough to 15th Century. But, according to CPI Inflation Calculator, $0.02 in 1635 is equivalent in purchasing power to about $0.71 today, an increase of $0.69 over 387 years. The dollar had an average inflation rate of 0.93% per year between 1635 and today, producing a cumulative price increase of 3,469.59%.
This means that today's prices are 35.70 times higher than average prices since 1635, according to the Bureau of Labor Statistics consumer price index. A dollar today only buys 2.817% of what it could buy back then.
- IDK how much trust I put in CPI though, considering dollar was introduced on July 6, 1785.
Catch me on the next episode of Fun facts wit BITOGers.