Proper way to check the oil? Getting frustrated

HearHear

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I check the oil once a week, and I’ve been doing it like this:

First thing in the morning, when the engine is stone cold, I look at the dipstick and the level seems to always be on the lower end of the crosshatch. Makes me nervous. But I added half a quart about two months ago, and don’t want to overfill it. I‘m not visibly losing oil anywhere.

Then recently I read you’re really supposed to check the oil this way:

After the engine is all warmed up, wait five minutes then check the level. I did this today, and the oil level is all the way full up the crosshatch area……

Waited a few minutes and checked again.…..

Back down to the bottom of the crosshatch area!

What am I doing wrong? What’s the proper way to check the oil?
 
The correct way is to check a warm engine 5 min after shutdown.
The engine oil will be higher when the engine is cold because all the oil has drained down into the bottom. When the engine is run, oil is forced into all those nooks and crannies that need lubrication and oil level measure typically drops. The reason they don’t check it immediately after shutdown is they want to give the engine oil time to settle down (hence the 5 min) but you want to check it to see what the oil level looks like in a warm (close to running) engine with the oil viscosity warm and flowing. If you think about it that’s the oil level that maters; oil in a running engine.

I’m always aiming towards the upper half of the crosshatch area. I personally don’t go full but that’s just me. According to the manual:
Adding 1 quart (1 liter) of oil when the reading is at the low end of the dipstick range will raise the oil level to the high end of the range marking.”

Even is you don’t have any leaks, oil is still consumed especially by the PCV (positive crankcase ventilation) and added to the intake and “burned off”. So oil is always being used. It sounds like your very much on top of it! 😉👍 I only check mine every fill-up.
 
Here is the section in the manual I have been referencing:

CHECKING OIL LEVEL​

To ensure proper engine lubrication, the engine oil must be maintained at the correct level. Check the oil level at regular intervals, such as every fuel stop. The best time to check the engine oil level is about five minutes after a fully warmed up engine is shut off.

Checking the oil while the vehicle is on level ground will improve the accuracy of the oil level readings.

There are four possible dipstick types:

  • Crosshatched zone.
  • Crosshatched zone marked SAFE.
  • Crosshatched zone marked with MIN at the low end of the range and MAX at the high end of the range.
  • Crosshatched zone marked with dimples at the MIN and the MAX ends of the range.
Note:
Always maintain the oil level within the crosshatch markings on the dipstick.
Note:
Use care when filling under hood fluids such as engine oil, washer fluid, antifreeze, etc., to minimize spillage onto the top of the engine. Any excess fluid that is spilled onto the top of the engine should be removed using compressed air or an absorbent cloth.
Adding 1 quart (1 liter) of oil when the reading is at the low end of the dipstick range will raise the oil level to the high end of the range marking.

CAUTION:
Overfilling or underfilling the crankcase will cause aeration or loss of oil pressure. This could damage your engine.

From the Wrangler 392 supplement manual:

Engine Oil — 6.4L Engine
For best performance and maximum protection under all types of operating conditions, FCA only recommends full synthetic engine oils that meet the American Petroleum Institute (API) categories of SN.
FCA recommends the use of Pennzoil Ultra 0W-40 or equivalent Mopar® engine oil meeting the requirements of FCA Material Standard MS-12633 for use in all operating temperatures.
 
The correct way is to check a warm engine 5 min after shutdown.
The engine oil will be higher when the engine is cold because all the oil has drained down into the bottom. When the engine is run, oil is forced into all those nooks and crannies that need lubrication and oil level measure typically drops. The reason they don’t check it immediately after shutdown is they want to give the engine oil time to settle down (hence the 5 min) but you want to check it to see what the oil level looks like in a warm (close to running) engine with the oil viscosity warm and flowing. If you think about it that’s the oil level that maters; oil in a running engine.

I’m always aiming towards the upper half of the crosshatch area. I personally don’t go full but that’s just me. According to the manual:
Adding 1 quart (1 liter) of oil when the reading is at the low end of the dipstick range will raise the oil level to the high end of the range marking.”

Even is you don’t have any leaks, oil is still consumed especially by the PCV (positive crankcase ventilation) and added to the intake and “burned off”. So oil is always being used. It sounds like your very much on top of it! 😉👍 I only check mine every fill-up.

I get that, so logically the oil level on the dipstick should be higher when the engine is stone cold. But the exact opposite is happening with me. The warm engine showed a full oil level on the dipstick. Cold, it only shows barely at the bottom part.

Have you added any oil since new? How much?
 
Oil level should read higher on a warm engine since the heat expands it as a liquid.
 
Oil level should read higher on a warm engine since the heat expands it as a liquid.
This 👆🏾 Mine shows the very bottom of the safe zone when cold, from day one. Check it 5 minutes after driving and its top of safe zone. 5 minutes after driving is when they want us to check, so that’s when I check and add if necessary. (I haven't had to add even though I was tempted to first time I checked when it was cold).
 
I get that, so logically the oil level on the dipstick should be higher when the engine is stone cold. But the exact opposite is happening with me. The warm engine showed a full oil level on the dipstick. Cold, it only shows barely at the bottom part.

Have you added any oil since new? How much?
Interesting :unsure:.... I haven't checked it cold only warm 5 min after shutdown per SOP. I took a look at my log and I added .25 quart at 480 mi, but it has been very steady at a bit over ½ way up the hatches.

I am learning more everyday, thanks guys. :)(y) most of what I know about engine oil comes from aviation, so I am not sure it translates. But funny enough in a jet engine we also check the oil 5 min after shutdown. In those engines I can see oil level updated every second, as the engine runs the engine oil will show low, but after you shutdown the oil drains down and the oil level starts to climb rather quickly hence the 5 min wait. And as @Dral97 said oil defiantly expands and I'm sure that plays a roll. In the end cold oil level seems kinda irrelevant from my perspective 🤷‍♂️, the only thing that maters is oil level 5 min after shutdown per the book.
 
Interesting :unsure:.... I haven't checked it cold only warm 5 min after shutdown per SOP. I took a look at my log and I added .25 quart at 480 mi, but it has been very steady at a bit over ½ way up the hatches.

I am learning more everyday, thanks guys. :)(y) most of what I know about engine oil comes from aviation, so I am not sure it translates. But funny enough in a jet engine we also check the oil 5 min after shutdown. In those engines I can see oil level updated every second, as the engine runs the engine oil will show low, but after you shutdown the oil drains down and the oil level starts to climb rather quickly hence the 5 min wait. And as @Dral97 said oil defiantly expands and I'm sure that plays a roll. In the end cold oil level seems kinda irrelevant from my perspective 🤷‍♂️, the only thing that maters is oil level 5 min after shutdown per the book.
Interesting. Mine is predicated on outside air temp (P&W). I had to look it up. Thanks for keeping me up on my limitations! I should have know that lol
 
I posted this a while back, since I was seeing weird readings. but I think it is something to do with the oil filter and how much goes in there after sitting…. Bypass and temp etc..
 
This 👆🏾 Mine shows the very bottom of the safe zone when cold, from day one. Check it 5 minutes after driving and its top of safe zone. 5 minutes after driving is when they want us to check, so that’s when I check and add if necessary. (I haven't had to add even though I was tempted to first time I checked when it was cold).
Thanks! I think we’re all on the same page now.
 
Interesting :unsure:.... I haven't checked it cold only warm 5 min after shutdown per SOP. I took a look at my log and I added .25 quart at 480 mi, but it has been very steady at a bit over ½ way up the hatches.

I am learning more everyday, thanks guys. :)(y) most of what I know about engine oil comes from aviation, so I am not sure it translates. But funny enough in a jet engine we also check the oil 5 min after shutdown. In those engines I can see oil level updated every second, as the engine runs the engine oil will show low, but after you shutdown the oil drains down and the oil level starts to climb rather quickly hence the 5 min wait. And as @Dral97 said oil defiantly expands and I'm sure that plays a roll. In the end cold oil level seems kinda irrelevant from my perspective 🤷‍♂️, the only thing that maters is oil level 5 min after shutdown per the book.
What does your log look like? Is it just a notebook or an app that you use to keep track of all these details? I’ve been driving for 30 years and never kept a log, but it sounds like a good idea…
 
What does your log look like? Is it just a notebook or an app that you use to keep track of all these details? I’ve been driving for 30 years and never kept a log, but it sounds like a good idea…

IMG_D4B1CDAF79FC-1.jpeg
Sure... I started out with a paper logbook, but then I just made my own spreadsheet in excel on my phone. I just take a picture of the gas pump totals and the dash with the dreaded "Fuel Economy" page with estimated mpg & odometer reading, and then update the excel when I get time using those photos. I'm a few fill-ups out of date, but that is kinda par for the course with all my logbooks.

Mostly I just want to see trends. Good news is MPG is slowly improving 😉. I have been driving 20 years and this is the first "log" I have ever kept. Once I have more data (5-10k mi) I'll post my trends.
 
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Checked mine tonight 6 hours after I parked in garage. I could still feel a bit warm when touched the engine cover. Checked couple times and the oil level was consistent and all the way to the top of the crosshatch area.

I’ll give it another check tomorrow morning before I leave and 5 minutes after home again. FYI, mine only has 2300 miles after a month and half.
 
As long as it is in the cross hatched area, you are fine for sure. I think if you keep checking it as long as the engine has been off long enough for oil to drain back into pan and keep it somewhere in the target range on the dipstick you will be fine. I also think that it is unlikely to cause any real damage even if the oil were a quart lower than bottom of dipstick or quart higher than top of dipstick. In my younger years, I've run into situations where I had to add 2 quarts to get oil back on dipstick and I've overfilled where it was well above target zone on dipstick.....Nothing happened... Not saying it is good, but nothing happened.

Variations like you are describing might have me scratching my head, but I bet if you keep checking it, you will find a pattern and it will settle down. Sounds like it will be fine.
 
Checked again this morning after the engine rested overnight and another time after driving 30 miles and I waited for a few minutes after parked as you guys suggested. Very consistent oil level across all three times, all the way up at the top of the crosshatch area, maybe a bit higher than the top bar.
 
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Warm engine with the shifter in Neutral and the parking brake on.

None of my Hemis ever burned any between oil changes
 
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