Help needed; 2019 5.3 oil level mystery

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LT1ZOB

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My 2019 Tahoe, new to me, I bought it a few weeks back. It's a CPO car with 18k miles on it now. Even though the dealer had done an oil change, I wanted to put in my own Mobil1 0w20. I checked the oil when I brought the truck home and it looked to be overfilled. Figured it was the perfect excuse to dump and put in my own. So a few weeks back I drained the pan, replaced the filter (AC Delco) and put in 8 quarts of Mobil1 synthetic. Was in a rush, never checked the dipstick after the oil change. Fast forward to tonight, I checked the oil level and it's well above the caged area. Did this once when cold, then since it looked overfilled, I went for a 30 minute drive, waited 15 minutes and checked again. Still overfilled. I've put a couple hundred miles on since the oil change and have no idea why it's "overfilled" again like it was when the dealer changed it. To answer the obvious, no smell or look of any contamination in the oil. Looks and smells like fresh, clean oil. Always put 8qts in my 16, never had this issue. Any thoughts?
 

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I never put the full capacity of quarts initially when doing an oil change. Some oil always remains in the engine, but usually only a little. Typically I'll short the fill by a quart (by the rated capacity), run the engine to build oil pressure, shut it off and let it sit so the oil drains back down into the pan. Then I check it and top it off.
 
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LT1ZOB

LT1ZOB

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Thanks. I get what you’re saying, but this seems to be more than just a little overfilled. I wonder if I have a fuel leak into the oil from the high pressure fuel pump? But I’m not really smelling fuel in the oil
 
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LT1ZOB

LT1ZOB

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Pretty damn overfilled. I just don’t get why

CA59449D-57C2-4EE3-B390-851DFB65EC62.jpeg
 

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Looks like about a quart over to me, but just a SWAG. Drain it off to the correct reading and monitor it. Maybe send in a sample to Blackstone if you think it might be getting contaminated.
 
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LT1ZOB

LT1ZOB

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Looks like about a quart over to me, but just a SWAG. Drain it off to the correct reading and monitor it. Maybe send in a sample to Blackstone if you think it might be getting contaminated.
I drained off a qt after work and it’s in the middle of the cage now. Also ordered a Blackstone kit for good measure. Thanks
 

woketradr

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Man I have a 2019 tahoe too and when I allow it to stay within the 2 dots I get an engine light related to low oil/ pressure.
If i do an oil change and add my 8 quarts its always reading high.
It doesnt make sense at all but clearly 8 quarts is 8 quarts.
And when it was reading between both dots I drained and measured and I was 1.5q LOW.
Soo..
 

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Man I have a 2019 tahoe too and when I allow it to stay within the 2 dots I get an engine light related to low oil/ pressure.
If i do an oil change and add my 8 quarts its always reading high.
It doesnt make sense at all but clearly 8 quarts is 8 quarts.
And when it was reading between both dots I drained and measured and I was 1.5q LOW.
Soo..

Got the right dipstick?

What specific code do you get for "low oil/ pressure?" Level and pressure are two different PIDs.

When you change your oil, add only 7 quarts, run the engine for a minute, then let the oil drain back down. After 15 min or so, check the level and top off as necessary.
 

jaxscuby

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swapped from 0-20W to 5-40W..
never liked a 20w motor oil..too thin for my liking.

The owners manual says 8.0 quarts.
I prefill the oil fiter.
I usually buy 2 jugs of rotella T6 5W-40 3.865 liters.
google says 1 lither = 1.06 quarts.
3.865 x = 7.73 liters = 8.79 quarts.

and its right at the top of the hatched area..full..
 
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