Oil Change - Hot or Cold and Oil Level Check - Hot or Cold?

BlueOvalFitter

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#1 - neither...warm. As for me, I'll change it first thing in the morning and just give it extra time to drain out...beats getting burned.

#2- No, the manufacturer probably has taken that into account. Plus, the capacity stated in the owner's manual...I find to be low...I always have to add about 1/2 quart over the stated capacity to get to the top mark on the dip stick...even sitting for a long while.

#3- what??? If it did, I don't believe its a significant amount of expansion. In fact, I find that the oil level reads a little lower after driving because some of the oil hasn't settled into the pan. Hence, many will state that you need to let the vehicle sit for several minutes before reading the oil level.

Don't get so hung up on it...it is a relative reading not an absolute. How do you know your vehicle is sitting 'perfectly level' when you check it?
Seriously? Do you think that you're smarter then the engineers?
My F150's engine dipstick reads 3/4 into the cross hatched area after adding the REQUIRED 6 qts. of oil. That's what my owners manual states, to add 6 qts. I don't add anymore oil to get it to the full line.
But, if it makes you sleep better at night, keep adding. :rolleyes:
 
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Nothing wrong with running the oil level to the Full line on the dipstick - something I've always prefefed when doing an oil change for reason mentioned earlier. Lots of high performance cars say in the OM to add a quart over Full for track days, and during a track day the engine isn't at high revs the whole time.
 
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Seriously? Do you think that you're smarter then the engineers?
My F150's engine dipstick reads 3/4 into the cross hatched area after adding the REQUIRED 6 qts. of oil. That's what my owners manual states, to add 6 qts. I don't add anymore oil to get it to the full line.
But, if it makes you sleep better at night, keep adding. :rolleyes:
I AM an engineer with OCD...and it's THAN not THEN...I don't care what you do, be a lemming if you want...
 
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Furthermore, how do you know that an 'engineer' spec the oil capacity stated in the owner's manual?

Being an engineer, I see where management (non engineers...aka, bean counters) override any decision or spec the engineer makes...for one reason or another...mostly cost.

Happens(ed) all the time at GM...
 
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Furthermore, how do you know that an 'engineer' spec the oil capacity stated in the owner's manual?

Being an engineer, I see where management (non engineers...aka, bean counters) override any decision or spec the engineer makes...for one reason or another...mostly cost.

Happens(ed) all the time at GM...
To add, the oil refill volume in the manual for the oil change may be based on a quick drain where some oil is left in the engine vs letting it drain for an hour or two. I always do long oil drains, and have to install a little more oil than what the OM or shop manual calls out in order to hit the Full mark on the dipstick. Once the total amount is known, just use that for subsequent oil changes if a long drainer.
 
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There's virtually no benefit in draining the oil hot and manufactures intend on you to check the oil in the sump when cold as hot oil expands a bit and you pour in cold oil not hot so cold measurements would be more accurate to what you put in. I drain from warm to room temp and it's fine. One could argue you'd get whatever residual oil out if you drain it when warm and let it drain long enough for the drips to almost end. i check my drain level by reading the bottle marks.

Dip sticks aren't super accurate and are more for just showing if there's oil in there or not. most will show nothing if its just a quart low. ford changed dip sticks to deceive people in a TSB. I really wish dip sticks were detailed in that they showed half quarts marks from empty to full. not just a general area it should be in.
 
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Dip sticks aren't super accurate and are more for just showing if there's oil in there or not. most will show nothing if its just a quart low. ford changed dip sticks to deceive people in a TSB. I really wish dip sticks were detailed in that they showed half quarts marks from empty to full. not just a general area it should be in.
There must be some pretty crummy dip sticks out there, all my cars show quite accurately the difference between full and one quart low, with halfway being one half quart difference. It's not at all "on-off" as you describe.
 
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There must be some pretty crummy dip sticks out there, all my cars show quite accurately the difference between full and one quart low, with halfway being one half quart difference. It's not at all "on-off" as you describe.
BMWs don’t have dipsticks 😛
 
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There must be some pretty crummy dip sticks out there, all my cars show quite accurately the difference between full and one quart low, with halfway being one half quart difference. It's not at all "on-off" as you describe.
I've checked accuracy of the dipstick in my vehicles and they are pretty accurate. If the level is on the Low mark and I add 1/2 qt it goes to the middle of the Low to Max (full) range, and add another 1/2 qt and it goes to the Max mark. I go through this routine on the first oil change so I know how the dipstick reads. Most dipsticks have hash marks of some kind between Low and Max/Full that can be used to get a more accurate reading. Example - 5.0L Coyote V8 dipstick (annotated). It's 1 quart between the Low and Max marks (two sets of markings for either cold or hot).

1626371817446.png


Photo of dipstick without annotations:

1626372100683.png
 
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ROLMAO, ..
Funny how this thread of all threads has gotten so much attention even the "grammar Nazi's are responding .. :LOL:

I can't say as I ever read anywhere that the dip stick coming from an auto manufacture caused an engine catastrophe. If there was one I would like to read about it. LOL IDK I don't read everything.


I want to know which exact "bean counter" from what auto manufacture over rides a development engineers design before it is approved by both the department head and the engineer and the engineering department who designed the part? LOL

this is fun itsa fricken dipstick, I mean is it that difficult to read and understand? Maybe that's where some of us Hot Rodders refer to a person that does not know much as a "DIP STICK... :p
hahahaha!

oh there are many BMW manufactured vehicles that have engine oil dip sticks
I own a couple 2002 and 2009 :p
 
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If we just followed the owner's manual, BITOG would be a very boring place.

There would be no "thick vs thin" or changing transmission fluid or any "lifetime" fluids.
Lifetime = ~20,000 miles because they sure do not have a very long life.
 
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If we just followed the owner's manual, BITOG would be a very boring place.

There would be no "thick vs thin" or changing transmission fluid or any "lifetime" fluids.
In Sparky16's world, there shouldn't - or wouldn't - be a discussion forum like this. Only reading of the manual.
 
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Like when people ask, Whats the best oil to use?. Seems everybody has their favorite brand and weight, and they all seem to work, so it;s appears there can be no wrong or bad brand as long as you have some oil in your vehicle. Clean or dirty also doesn't seem to make a difference. Change it at 2500,3000, 5000, ofr 10,000 miles and the motors still run.,,
the best oil? the
Drain oil when still pretty warm, and let drain awhile (30 min) while removing and installing the oil filter, and checking over engine, etc.
Install enough oil to get the level near the Full mark on the dipstick ... that's after running the engine a few minutes to fill the filter and galleries.
Check oil level cold after the car has been driven and has sat all night - and do final oil level adjustment to the Full mark on the dipstick.
That is too much effort.
 
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ROLMAO, ..
Funny how this thread of all threads has gotten so much attention even the "grammar Nazi's are responding .. :LOL:

I can't say as I ever read anywhere that the dip stick coming from an auto manufacture caused an engine catastrophe. If there was one I would like to read about it. LOL IDK I don't read everything.


I want to know which exact "bean counter" from what auto manufacture over rides a development engineers design before it is approved by both the department head and the engineer and the engineering department who designed the part? LOL

this is fun itsa fricken dipstick, I mean is it that difficult to read and understand? Maybe that's where some of us Hot Rodders refer to a person that does not know much as a "DIP STICK... :p
hahahaha!

oh there are many BMW manufactured vehicles that have engine oil dip sticks
I own a couple 2002 and 2009 :p

Now that you got that off your chest you should give us the hot rodder perspective in a more clear and understandable language without lol’s and emojis.
 
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