Anyone overfill the crankcase on purpose?

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35
Location
Mississippi
Originally Posted by mpgo4th
I'm about 500 miles away from servicing my wife's 2018 with a 2.0 Turbo GDI. I'm thinking about running a smart change box of Havoline Pro DS 5w30 for this OCI. The manual says the car holds 5.7 quarts while the box of oil has 6 quarts in it. It seems near impossible to get the oil perfectly filled to that amount so I'm thinking I'll just pour all 6 in it. I know it wouldn't normally hurt anything but with the direct injection causing fuel dilution I'm second guessing putting the oil up the stick to start with. Any thoughts?
I was taught that a little bit under full is a better than little bit over full. Do to potential foaming if you're over full which can affect the film strength of the lubrication. But I wouldn't think anything under a half qt. would make a real effect either way.
 
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873
Location
AR
I am an avid overfiller.....not so much on purpose....but I do it often - up to a quart or so. (all that extra liquid cooling helps my engine) smile
 

mpgo4th

Thread starter
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438
Location
VA
Due to an issue at walmart, I am not going to be using the 6 qt box after all. I'll be going back with the Federated full synthetic 5w30 thats in the car now. It's in qt bottles so 5.7 qts will be easier to add.
 
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34
Location
USA - WA
Used to overfill some of our older vehicles on purpose as they were known to use some oil. In the case on a trip if they were to use some there would be be more capacity before it'd get low. My dad ran our old Dodge van 1 quart overfull for 33 years with no issues until we sold it. I don't buy much into the oil foaming, crankshaft whipping the oil thing. Not all of the oil sits in the oil pan when its running like it does when it's shut off. A surprising amount of oil rests in the cylinder head/heads, oil galleys, etc when running. I don't bother on any newer vehicle but I know it won't hurt a thing if I add a bit much on accident. A few months back I was spinning the oil pump of a Ford 390 on the engine stand priming it with a drill. I only put 3 quarts in to start. It sucked all of that up and it sat in the heads/lifter valley. 4 quarts it sucked air after 10 seconds and lost oil pressure, 5 quarts worked but still sucked air after a while. 6 quarts of course was fine. I can only imagine what it would do if it were low on oil and cornered hard. This was at 70 degree temp with 10w30 oil, so not like it was overly thick taking forever to drain to the pan. I know a lot of newer engines are physically a lot smaller and less oil can be held in the head area but still, similar things will happen.
 

MolaKule

Staff member
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21,702
Location
Iowegia - USA
Originally Posted by hatt
Originally Posted by Kira
>An educated friend mentioned that the Small Block Chevy was "known" to accept an extra quart of oil. >I've read that engineers have a range of driveway angles they use in designing sump levels. >Me? I don't know. My car calls for 6.1 quarts of oil and I short it. Does that count?
Yeah, that one would be getting 6. I think these listed capacities are just to make changing oil look harder than it is so you take it into the dealership. Every sump would be just fine with 1/2 quart increments.
The stated volume is not to complicate oil changing but to make sure excessive foaming does not occur. The OEM is simply stating the safe volume of oil in the sump so you don't get too much entrained air in the oil, since air is not a lubricant. Additionally, most OEM's state crankcase volumes in metric units so the stated US Liquid Volume's are for our convenience.
 
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362
Location
Pikes Peak region
Lets say I find out my car take take another quart of oil or as some have said ... " I have run over fill in many cars and not damaged them." *A person claiming they didn't blow up their motor isn't a compelling enough benefit to sell me on adding oil well above the line. grin2 Is there a gain of some sort I'm missing here ? Oil temp has has a specified range for optimal performance so it wouldn't seem an extra quart does much of anything. Maybe some see the extra volume as a way to extend oci ?
 
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586
Location
Raleigh NC
Resurrecting this thread to relate this story. My daughter took her 1.5T '17 Malibu to a shop to have the oil changed (told her to bring it here but she won't listen, thinks she's imposing or something). 2 days later, it tripped a P2097. The oil was filled a little over 1/2 qt high on the dipstick, and apparently it's well known (PIP5535B) that this can cause the P2097 on this car through some strange interaction (oil smoke dirtying the cat/sensors maybe?). So this is one engine you do not want to overfill.
 
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799
Location
Cali
This is all personal preference. Some say you can overfill up to 1 quart and still be fine. As for me, I do not overfill. Maybe slightly over the full but that is it. No point in overfilling because it is a waste of oil. Unless you know your engine burns oil then I would overfill.
 
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35,460
Location
NY
I did for years in two vehicles that called for 4.5 quarts. I put 5 quarts in, not to have open quarts or 5 quart jugs laying around.
 
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2,231
Location
SE MI
My dad's old school and would always throw in 1 qt more than what the book asked for, and it seems to have worked for him.
 
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13,229
Location
1/2 hr N.E. of Detroit
Originally Posted by mpgo4th
I'm about 500 miles away from servicing my wife's 2018 with a 2.0 Turbo GDI. I'm thinking about running a smart change box of Havoline Pro DS 5w30 for this OCI. The manual says the car holds 5.7 quarts while the box of oil has 6 quarts in it. It seems near impossible to get the oil perfectly filled to that amount so I'm thinking I'll just pour all 6 in it. I know it wouldn't normally hurt anything but with the direct injection causing fuel dilution I'm second guessing putting the oil up the stick to start with. Any thoughts?
Never. I'd rather be a half-quart short of a five quart crankcase, than a half-quart over.
 
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705
Location
Indiana
I actually purposely overfill my 25hp kohler on my zero turn, I go up a steep hill with it and have been afraid of oil starvation. Almost 1000 hours of this has caused no issues. Judging by the fact that it's a vertical shaft engine (connecting rods wont dip into oil in pan) and the fact that I can see nothing that would cause it to froth, i am comfortable doing thos on this particular engine
 
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245
Location
Illinois valley
My 2018 Mazda CX-5 calls for 4.5 liters/4.8 quarts and shows about 1/3 past the low mark. All 5 quarts still doesn't reach the full mark. I empty the jug when the oil level drops close to the low mark. I let the dealer do the first oil change and they filled it past the full mark. I guess they were making up for the MAZDA VALUE filter they gave me instead of the OEM filter. Who is best qualified to change my oil? ME
 
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1,051
Location
WV
I under fill mine on purpose. I have 2 MB's which take 8-9 qts. Filling them to the top line overwhelms the pcv system.
 
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3,148
Location
Western S.C.
Originally Posted by loneryder
... I have 2 MB's which take 8-9 qts. Filling them to the top line overwhelms the pcv system.
That's with the no more than the specified volume? What's the result? Oil consumption through PCV?
 
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4,597
Location
Manchester, England
If the owners manual says 5 quarts but you fit a filter that is 0.5 qts larger than the original factory filter and you then add 5.5 qts to reach the full line on the dipstick, would it be considered overfilled? Do we judge by the quanityt listed in the book vs. the quantity you pored in? Or do we judge by the dipstick regardless of how many quarts we actually added? I replaced my 719/5 with a 950/4 and now require 5 litres instead of 4 to reach 'full' on the disptick - is this considered 'overflled'
 
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2,191
Location
South Carolina
Originally Posted by loneryder
I under fill mine on purpose. I have 2 MB's which take 8-9 qts. Filling them to the top line overwhelms the pcv system.
Agree. If it's in the range on the dip stick, I'm ok with that. A little under is better than a little over.
 
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55
Location
SoCal
Overfilling can raise the oil level high enough that the crank "whips" the oil into a frothy mess. It can cause low oil pressure issues. It also can cause a TON of parasitic drag on the engine. It can kill power and increase fuel consumption. Saw a video of a Ford 6.0 diesel that the owner overfilled. Capacity was 2 gallons, there were 5+ gallons in the engine. It was fine until it hit 65-70 mph, then it felt like someone grabbed onto the bumper and bogged her down. Correcting to the proper level solved.
 
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