gtroth

First, I believe my oil level sweet spot is on the low side. If I fill to mid level on the dipstick, I will need to add a liter after ~750 highway miles. If I fill it to just register on the stick, I need to add a liter after ~1500 miles, so I run it there.
Oil level gauge never budges, and oil temperature always runs pretty cool, well below the 8:00 mark.
Until once a couple of days ago. Ran an errand when it was >100 deg. F outside, and noticed that when idling, both gauges read like I always thought they should - oil temperature approaching 9:00 and the oil level at around 4:00.

Any idea what all this means?

Falcondrivr

That's pretty close to what I see, so I'd say it's working properly....

gtroth

On the very hot day it seems to have behaved like I thought it should.
Which makes me wonder why it doesn't always behave that way - usually behaves as though it is running cold, even after my daily 35 mile highway commute.

RocketJohn

So the less you fill it, the less it consumes?

gtroth

Yes. Half on the dipstick seems to be overfilled for me.

Slow Guy

I'm sorry, but that just doesn't make sense. The only way that would compute is if you're adding oil when the oil reaches different levels on the dipstick, depending on how full you left it originally.

RocketJohn

I don't know why the engine would consume more or less if there is such a slight variation in fill level.

gtroth

It's as if the oil from the half way point on the dipstick down to ~1/8" from the tip is blown out. Just like many who report that filling to the top of the dipstick twist gets blown out so they run it at half way.

vincer77

As the oil heats, it increases volume so one would expect the oil to show higher, though not by as much as you are experiencing, also, it should affect the dipstick and oil guage equally. Did you check the stick on that hot day? My oil temp rarely passes the second mark on the guage. Maybe the lack of undertray causes our engines to run too cool?

My oil guage did not correspend to the dipstick oil level when I bought the car. During my first oil change, I bent the arm of the oil level sender unit so it would read higher. After a couple of months, it started exhibiting the same behavior. The arm is pretty stout, so I can not imagine that the force exerted by the oil level could have bent it back. I bent it again during my last change, and it is reading only slightly less than the dipstick.

Slow Guy

This is the part that doesn't make sense,

This part makes sense. The "happy spot" on mine is 1/2 down on the stick but that doesn't mean that if I only fill it to 1/4 on the stick it will take longer to get to the bottom than if I fill it to the 1/2 point. That just defies logic.

gtroth

But if you fill yours to the top it will consume oil faster until it gets to the sweet spot. Just like mine, except my sweet spot seems to be lower than yours.

Mike J

Yeah most of these cars like a certain level of oil - most in the lower third. If its above that, then lots of cars consume untill hitting that sweet spot where then the oil consumption seems to slow down.

I usually find thay the sender level reads low - i usually adjust it on most cars that i work on.

Oil expansion is normal - i have seen cars go from 1/2 full to full due to temp increases - that is a barely wamr to coming off the track.

Cheers

Mike

Ed Hughes

If you are overfilling, and it gets ingested where it shouldnt, you'll know it-just keep an eye on the rear view mirror. The level on your dipstick will not effect oil consumption, unless you really do overfill.

No HTwo O

Maybe your thermostat is stuck open????

ca993twin

The oil level gauge (and the dipstick) only read correctly when the engine is VERY HOT, at idle and level.

It sounds like your gauges are working just right.