Underfilled sump for short trippers

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So someone recommended to me that I run my car a qt. low because it would be easier for the oil to get up to temp. The heat has been getting warmer faster, by a bit, but it might also be the weather outside. The engine seems to be running a little smoother, but it’s probably just me.

Question
If the oil is just below the Fill line, what problems can I be causing?
 
quote:

So someone recommended to me that I run my car a qt. low

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Makes some sense to me. Get the oil up to temperature sooner, boil off the moisture and fuel quicker. Why not? Be nice to have a oil pressure gage to keep an eye on things.
 
I guess you would need to define "short tripper" more clearly.

Less than 5 miles? For short distances. Yeah, why not?
 
Funny, all the Audi 1.8t owners jumped onto the "biggie" filter bandwagen when it was recommended to increase capacity and reduce sludge. Being the independant BitOG thinker that I am, I said hey, maybe short trippers will get MORE sludge with more oil to heat. In that engine, it sludges from oil lines getting too hot....but it could be better to use the smaller filters.
 
I guess I will just keep it normal then. Short trips mean 1/2 mile once or twice a week, and 2.5 miles the rest of the weekdays, both of these twice a day, and various travels.

Longer trips occur during the weekend, but the only way to avoid stop lights every 1/2-3/4 mile is to pay money to get on the tollway. I am right at the Fill line, and was just wondering what you guys thought about going lower than that. I know people have gone too full but I was just wondering what running a little low would do. Can anyone give any reasons aside from that’s stupid or don’t do that.

I am driving because of the insurance policy that my school’s company has me on. I can’t really change it, and can’t change my mode of transportation.
 
But what about the parts in a motor that are splash lubricated? Such as cylinder walls, piston skirts, wrist pins, and in some cases the cam lobes and lifters. More oil fling around in a lower RPM motor is a good thing IMO.
 
I think it is a great idea, but as Hirev says, maybe the level is important for splash lube. Hmmmm, there was an old trick to save water by putting a brick in your toilet tank. Hey, put a brick in your oil pan. Then you can run a quart short and still read full on the stick.
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Anyway, if you are going to run it low, keep it near the lower end of the safe zone.
 
splash lube is generally achieved by oil being expelled from bearings, lifters etc and NOT from the crank dipping in the sump. every winter i ran my harley with the level of oil on the "add" mark, got warmer quicker, still got the bike after 14 years, no oil use
 
I recall a mileage article by Smokey Yunick where he was advising to remove some oil to minimise friction.

He stated that you could run the oil level just above the "add" mark safely (or the add mark would be somewhere else), and if the manufacturer said that the diff/gearbox (manual) oil had to be within a 1/2" of the bottom of the fill hole, then run it that way.

Didn't offer much, but it would certainly speed up the oil heating, and minimise drag/windage...and safely.
 
It’s a very low RPM motor, but I don’t see how an extra 1/4 inch in the sump could rob anything but a 1/4 inch of the sump from starvation, unless I am driving the car at a very weird angle, and that 1/4 inch could possibly rob the oil pickup of oil. I will hit the sump up with some more LC, and see how she goes. the filter is the same size as what was on it, and this will probably be the last OCI I get to enjoy. It will be passed on to someone for free, or it will get junked.

[ February 23, 2006, 02:30 AM: Message edited by: Shaman ]
 
You run the risk of the oil pump sucking air if you get in a situation that moves the oil in the pan away from the pickup. Take a corner too fast and you might spin a rod bearing. The amount of energy it takes to heat a pound of oil is nothing compared to the energy it takes to heat a 300 - 600 pound engine.
 
I used to just let my car run without checking the oil until the oil light came on. Heck, if it was really important to keep the oil up to the dipstick fill line, they would make the oil light come on when the oil hit the bottom of the dipstick, right? And it took about 4-5 months for my oil to get low enough for the light to come on, so it served as a handy oil change reminder. I figured it was like that on purpose.
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On the plus side, it never took very long for the old oil to drain out! All one quart or so of it.
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My car survived a few years of this treatment, so I doubt you'll do irreparable harm to yours. But I'd keep it above the fill line for sure.

(This was pre-BITOG by the way... oil stays topped up now!)
 
Vilan, it is not like that anymore in most cases. Oil light means low pressure(less than 10lbs, on some, less than 7lb) these days. That means you are running extremely low on oil or your motor needs something done if it comes on steadily or flickers when just idling, and your going to ruin your motor if you arent paying attention. Heck, my dad towed with my moms E150 and when he got back it was 2.5qts low, oil light never came on. He wasn't thinking about oil level at the time as he is used to vehicles which use none, not one that uses a qt every 500-700 miles when towing in 100°F+ heat.

I say don't run less than halfway between add and full.
 
Have done it for years. On a '75 VW rabbit, ran just enough oil to see it on the tip of the dipstick. After 269,000 pizza delivery miles, I got tired of the car and parked it in the pasture for the cattle to use to scratch their backs. I think that running minimum oil is an alternative to long OCIs. As long as the oil pump isn't aspirating air, I don't see the problem. Sounds scary though .. doesn't it.
 
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