Is it better to fill up to the high mark?
- Thread starter jsw
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More oil is better. If you can hit the mark accurately, then do it. Most guys underfill a bit, run the engine, let it settle down and then top-off. Usually, the hash mark area on the dipstick is equal to one full quart, maybe a lil less.
I like to measure in a cold engine, and allow a little bit for the oil to expand when hot.
I like to measure in a cold engine, and allow a little bit for the oil to expand when hot.
I always overfill to about 1/8-1/4" above the fill line. Now that I don't burn any oil throughout the OCI it probably isn't necessary, but I do it anyway.
I always add 1/2 quart to the manufacturer's recommendation. Have been doing it for over 300,000 miles worth of oil changes on 5 cars.
Originally Posted By: Vizzy
1/2 qt over probably isn't a problem but I wouldn't put much more than that over the mfr recommendation...excessive over filling can damage your cats and or certain oil seals.
Excessive overfilling will also cause the crankshaft to airate the oil and cause drag on the crankshaft.
1/2 qt over probably isn't a problem but I wouldn't put much more than that over the mfr recommendation...excessive over filling can damage your cats and or certain oil seals.
Excessive overfilling will also cause the crankshaft to airate the oil and cause drag on the crankshaft.
1/2 way between the low & high marks then check it hot and see where it's at. Oil expands like transmission fluid.
Filling too full is a bad plan, you can drag the crank or dip a rod cap and churn up the oil into a foam and the PCV system will possibly suck out a quantity of oil giving a false oil consumption.
Filling too full is a bad plan, you can drag the crank or dip a rod cap and churn up the oil into a foam and the PCV system will possibly suck out a quantity of oil giving a false oil consumption.
Yup.
Let's not get too carried away with the assumptions of the crank aerating the oil. While it can happen, it typically requires a fairly excessive overfilling. Also, many of today's engines use windage trays to help keep oil spray and slosh away from the crank. Also keep in mind that the oil level is only that high until you start the engine. Then there are at least a couple quarts in the crank, oil galleys and the top end.
Generally speaking, overfilling by a quart or less will have no ill effects.
Generally speaking, overfilling by a quart or less will have no ill effects.
Get to know you engine.
A four cylinder I had some years ago would use a 1/2 quart then stop. If I added back up to the full mark, it'd use the 1/2 quart and stop.
That was summer. Winter it didn't use at all.
My current engine calls for 4-1/2 qts.
I add five and be done with it. My Mobil-1 comes in 5 qt jugs-it all goes in there.
No use issues.
A four cylinder I had some years ago would use a 1/2 quart then stop. If I added back up to the full mark, it'd use the 1/2 quart and stop.
That was summer. Winter it didn't use at all.
My current engine calls for 4-1/2 qts.
I add five and be done with it. My Mobil-1 comes in 5 qt jugs-it all goes in there.
No use issues.
My Aerostar calls for 4.5 qts, I add 5 qts unless I have an open bottle of oil with half a qt. Then it will get 4.5 qts. I now have about 185,000 miles on it and it runs like a top. I would say being 1/2 qt over the full mark is not a problem. I would not go any more than that though. JMO
Anywhere between add and full is safe. However; I run mine at near the full line and never go more than 1/8 inch or so over the full line. Over filling that just is a waste of oil IMO.
Patman
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I've been overfilling both of my cars for many years now with no problems. Like The Eric said, it takes a lot of extra oil in order for the crank to aerate the oil. Anytime you see a capacity listed in an owner's manual, you know the engineers thought about the fact that many people will round up that number (ie the capacity is listed as 4.5 qts but many people will just throw in 5) and they also realize that some might try to push it even further. So IMO, I don't think there is a single car made out there that would give a problem if you ran it a 1/2 quart over. I think in most cases you'd need to add at least 1.5 to 2 quarts more before you'd even begin to have an issue. I run a half quart high in my wife's Civic and a full quart over in my Corvette (the manual even says you can add one extra quart if you're racing the car, so I saw no reason why I could not do it for regular street driving too)
I don't think overfilling is a waste of oil at all. The higher amount means it will not degrade as quickly (for instance, the TBN will not drop as fast) and in theory that should mean a cleaner engine too. Also, with the same amount of wear metals going into a larger amount of oil, that means it is spread out more so those wear metals in turn won't be as abrasive as they would with a lower amount of oil. The larger amount of oil should run cooler oil temps under hard driving conditions too.
I don't think overfilling is a waste of oil at all. The higher amount means it will not degrade as quickly (for instance, the TBN will not drop as fast) and in theory that should mean a cleaner engine too. Also, with the same amount of wear metals going into a larger amount of oil, that means it is spread out more so those wear metals in turn won't be as abrasive as they would with a lower amount of oil. The larger amount of oil should run cooler oil temps under hard driving conditions too.
Originally Posted By: dwendt44
Get to know you engine.
jsw, I'm a newbie to BITOG myself, but I'll add a related vote to dwendt44's comment ... "Check with your owner's manual."
My new-to-me 1995 M-B E320 is pretty specific about the oil level check procedure. With oil fully warmed-up (which is a 20+ minute drive for me), stop on a level surface, wait 3-5 minutes before checking level. Do not exceed full mark on dipstick, excess oil must be removed, etc.
Never had such detail before, but it is my first German car
Works out for me to check when I make a gas stop after a run from work back home.
Anyhow, with my level indicating nearly full using the procedure described, it looks like somewhat of an overfill if I check it after being parked overnight, when everything has drained back into the sump.
Get to know you engine.
jsw, I'm a newbie to BITOG myself, but I'll add a related vote to dwendt44's comment ... "Check with your owner's manual."
My new-to-me 1995 M-B E320 is pretty specific about the oil level check procedure. With oil fully warmed-up (which is a 20+ minute drive for me), stop on a level surface, wait 3-5 minutes before checking level. Do not exceed full mark on dipstick, excess oil must be removed, etc.
Never had such detail before, but it is my first German car
Works out for me to check when I make a gas stop after a run from work back home.Anyhow, with my level indicating nearly full using the procedure described, it looks like somewhat of an overfill if I check it after being parked overnight, when everything has drained back into the sump.
Originally Posted By: The_Eric
Let's not get too carried away with the assumptions of the crank aerating the oil. While it can happen, it typically requires a fairly excessive overfilling. Also, many of today's engines use windage trays to help keep oil spray and slosh away from the crank. Also keep in mind that the oil level is only that high until you start the engine. Then there are at least a couple quarts in the crank, oil galleys and the top end.
Generally speaking, overfilling by a quart or less will have no ill effects.
Windage tray's are designed to work only if the oil is at the proper level. If oil level is above the tray the purpose is defeated.
Let's not get too carried away with the assumptions of the crank aerating the oil. While it can happen, it typically requires a fairly excessive overfilling. Also, many of today's engines use windage trays to help keep oil spray and slosh away from the crank. Also keep in mind that the oil level is only that high until you start the engine. Then there are at least a couple quarts in the crank, oil galleys and the top end.
Generally speaking, overfilling by a quart or less will have no ill effects.
Windage tray's are designed to work only if the oil is at the proper level. If oil level is above the tray the purpose is defeated.
Originally Posted By: AMRoberts
My new-to-me 1995 M-B E320 is pretty specific about the oil level check procedure. With oil fully warmed-up (which is a 20+ minute drive for me), stop on a level surface, wait 3-5 minutes before checking level. Do not exceed full mark on dipstick, excess oil must be removed, etc.
Anyhow, with my level indicating nearly full using the procedure described, it looks like somewhat of an overfill if I check it after being parked overnight, when everything has drained back into the sump.
Regarding your MB engine, which is M104, it should not be filled to Max. on dipstick. A while ago MB stated in one of its bulletins to reduce the oil capacity by 0.5L in M104 since they are prone to leaks from timing cover. Best situation would be between Min. and Half on dipstick, being on Max. I think is considered overfill. So instead of using 7L, use 6-6.5L. In my case I have been using 6&1/3 bottles which brings the level slightly below half-way on dipstick, and never had to add oil between changes (6 months/7.5k miles).
My new-to-me 1995 M-B E320 is pretty specific about the oil level check procedure. With oil fully warmed-up (which is a 20+ minute drive for me), stop on a level surface, wait 3-5 minutes before checking level. Do not exceed full mark on dipstick, excess oil must be removed, etc.
Anyhow, with my level indicating nearly full using the procedure described, it looks like somewhat of an overfill if I check it after being parked overnight, when everything has drained back into the sump.
Regarding your MB engine, which is M104, it should not be filled to Max. on dipstick. A while ago MB stated in one of its bulletins to reduce the oil capacity by 0.5L in M104 since they are prone to leaks from timing cover. Best situation would be between Min. and Half on dipstick, being on Max. I think is considered overfill. So instead of using 7L, use 6-6.5L. In my case I have been using 6&1/3 bottles which brings the level slightly below half-way on dipstick, and never had to add oil between changes (6 months/7.5k miles).
I couldn't bear to do an oil change and not fill it up to the full line.
That said, it is perfectly OK to be 1/2 qt down.
That said, it is perfectly OK to be 1/2 qt down.
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