Do some quick searching and basic math. Your well north of 95% suggestion is just plain wrong. He is correct there's typically a 10-20% difference between wet and dry fill and usually more with dry sump engines. When you drain your 8 quart tundra that took 9.8 quarts to fill initially there's 1.8 quarts remaining hidden in the engine that didn't drain. Same with a 5.5qt dry fill 2.5L subaru that only takes 4.5 wet.
Topping up a fill with a different brand
- Thread starter dwasifar
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There is absolutely a significant amount of motor oil left over in an engine, after draining all the oil and removing the oil filter. Refer the the service manual for your car, and you will find two fill amounts for oil fills, typically as @JavierH19 stated, referred to as "dry" and "wet". The "dry" fill refers to the total oil capacity of an engine, and how much is required to fill and engine after a rebuild, after all oil is drained out. The "wet" fill shows the oil required after draining and removing the oil filter, to bring the oil level back to fill.
The Service Manual for the Subaru FB25 engine in an Outback that I used to own, showed total oil capacity at 5.9 quarts called for 5.1 quarts for an oil and filter change. A Mercedes I used to own, with a 5.5 liter engine, had a total capacity of 8.3 quarts, but only 6.9 quarts were required for an oil and filter change. I've seen spec's for diesel engines that show well over 2 quarts difference between total capacity (dry) and oil change (wet) fills. This explains why oil on the dipstick can look dirty, right an oil change, after running the engine, particularly for diesel engines.
Like JavierH19 said, look it up if you don't believe it
That seems reasonable, but how do you know how much is in it? Do you measure it out?
That is some Imaginary Data. Lot of that going around these days, LOL.
Regardless, my carefully chosen mixes have resulted in stellar UOA, but they usually had a similar visible AW/DP elements.
- Arco
I base it purely on the dipstick.
I pour in several quarts and as it's getting close to full, I check the dip stick, add a bit more oil, check the dipstick, etc. After a start and check for leaks, I always have to add a bit more oil while again checking the dipstick.
wemay
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No issue whatsoever.
I have a spare 5quart jug where I add any extra new oil to that is left over from an oil change. On my Honda, I typically have .2 of a quart left over. No idea what is in there from all the oil changes but I use it once its full.
Theres been plenty of frankenbrew UOAs over the years that have shown great results. I wouldnt worry about it.
Theres been plenty of frankenbrew UOAs over the years that have shown great results. I wouldnt worry about it.
The obligatory BITOG "It's Totaled" comes to mind.
I've mixed/matched brands and viscosities to use up quarts for at least 45 years. The oil user/burner vehicles will most likely get topped up with multiple versions until my stash is all one flavor. Even then it might be a different viscosity.
If you use HPL EC30 it will inevitably be mixing with whatever else you have. In theory you "could" probably run all EC30 but I don't think hat is recommended by anyone here or the manufacturer.
I've mixed/matched brands and viscosities to use up quarts for at least 45 years. The oil user/burner vehicles will most likely get topped up with multiple versions until my stash is all one flavor. Even then it might be a different viscosity.
If you use HPL EC30 it will inevitably be mixing with whatever else you have. In theory you "could" probably run all EC30 but I don't think hat is recommended by anyone here or the manufacturer.
Seriously? Its real life data. You don't think 10's of millions of vehicles have had numerous mixes without issue?
You have a lot more patience than I do, apparently.
If I know the car takes 5.5, I pour in a full jug and then measure out a pint from the Partial jug, using the plastic measuring cup I keep in the garage for that purpose. Then I run for a few minutes and check it. Usually I find it's good to go.
You could still do that. The "extra oil" would always come from the same jug. If you change oil regularly it won't get all that old before its used up.You have a lot more patience than I do, apparently.
If I know the car takes 5.5, I pour in a full jug and then measure out a pint from the Partial jug, using the plastic measuring cup I keep in the garage for that purpose. Then I run for a few minutes and check it. Usually I find it's good to go.
I just prefer to turn over all the oil with every change.
I have a jug with a few different fresh left over oils in it and use that to top up but only on engines with older and dirtier oil in them. That mix (imho) is already better than what's in the engine.
I don't worry about it.
I do pour in the open jug first and top off with the new jug. It helps avoid the problem of old oil hanging around the garage for a long time.
It is a fact that mixing oils could cause the chemistry/additive pack to not work perfectly well together, this could cause additional wear but nothing to really worry about especially in the short term. I warned about this for a while now because I noticed it in UOA's where wear metal was slightly higher with mixing or when switching brands of oil, this is why when you do a UOA after switching oils do it on the second run because some old oil remains in the engine.
Anyways not long ago Lake Speed JR showed pretty much the same thing.
In my opinion don't mix unless you are topping up towards the end of an oil change on an oil burner or emergency purposes, just stick to the same brand, buy an extra 5 quart jug.
But also keep in mind millions of cars on the road go to quick lubes where they use the cheapest bulk oil they can get which likely changes brands often and you will see these vehicles often times with 200,000+ miles.
Anyways not long ago Lake Speed JR showed pretty much the same thing.
In my opinion don't mix unless you are topping up towards the end of an oil change on an oil burner or emergency purposes, just stick to the same brand, buy an extra 5 quart jug.
But also keep in mind millions of cars on the road go to quick lubes where they use the cheapest bulk oil they can get which likely changes brands often and you will see these vehicles often times with 200,000+ miles.
I have two vehicles that take 4 1/2 qts, another & daughter's bronco that take 5 1/2 qts. So I almost always have some frankenbrew in stock for partial fillups and on occasion a full change on frankenbrew. One vehicle has 235,000 miles and another 125,000 and never an issue as both are always on full mark at each 5,000 mile OCI.
Mix with no worries.
^^ This exactly. My sumps are at least 20% old best I can tell.
So you would need to run the same oil for pretty much ever to matter, then hope the OEM did not change the formulation.
I also don't worry about it.
I see where i went wrong. I wasn’t specific, and I didn’t think about oil coolers. I probably should have said that I don’t think my cars or similar would hold such large quantities after a drain. So, my bad.
Also wasn’t thinking of diesels. A 6.0 Powerstroke takes about 15 qts. for an oil change, and has an oil cooler. Probably withholds more oil than the average 4-cyl gas engine. For that matter, if you have a Cummins Big Cam 400, it’s probably going to retain some oil.
Edited to add: so far, I haven’t been able to find dry capacity of my engines.
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Next Oil change, I'm mixing 1 quart of hpl 0w16, one quart of hpl engine cleaner, and 3 quarts of Castrol 0w 20. I don't like wasting oil. Lord help me
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