First Oil Change

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ReaperHWK

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Got this truck (around Oct 2020) and it's been great. 104k when I got it, it's like 107k now. Oil life is around 55%.

At what oil percentage do you guys usually change the oil? I'm going to do it myself and was thinking about changing over to full synthetic Mobil 1(I'm sure it has the regular conventional oil in it for the last 107k miles). The car doesn't drive much so I figure the synthetic is better for this situation. Used to be a rental truck now it's in retirement, haha.

I also read some people say it's bad to switch to synthetic after a long use on conventional, but then I see tons of videos saying there is no issue.

Anyone switch to synthetic after a LONG time on conventional?

Also, will the OLM know somehow that the oil is synthetic and will keep the percentage higher than if it was on conventional? I'm not sure how that works.
 
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Jason in DLH

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Got this truck (around Oct 2020) and it's been great. 104k when I got it, it's like 107k now. Oil life is around 55%.

At what oil percentage do you guys usually change the oil? I'm going to do it myself and was thinking about changing over to full synthetic Mobil 1(I'm sure it has the regular conventional oil in it for the last 107k miles). The car doesn't drive much so I figure the synthetic is better for this situation. Used to be a rental truck now it's in retirement, haha.

I also read some people say it's bad to switch to synthetic after a long use on conventional, but then I see tons of videos saying there is no issue.

Anyone switch to synthetic after a LONG time on conventional?

Also, will the OLM know somehow that the oil is synthetic and will keep the percentage higher than if it was on conventional? I'm not sure how that works.

We picked up our ‘15 Yukon 6.2L last year with about 60k miles and I switched to full synthetic at that point. It now has 65K. Not a good example, sorry.

My ‘07 Yukon 6.2L we purchased with about 70k miles on it. I didn’t switch to full synthetic until about 100K miles and I have about 130K on it now with no issues.

Last oil change my OLM was still at about 50%, but was coming up at 1 year, so I changed it. I usually change at the high end of suggested service interval found in the manual (1 year or 10,000 miles on the ‘07. Can’t remember the ‘15 right now, but must be similar).
 

Bill 1960

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OLM has no way to determine what kind of oil is used.

I do not accept the marketing hype about extended oil changes with synthetics. Oils don’t wear out, they become contaminated from combustion byproducts and additives get depleted from same.

I often DO use synthetic, for the advantage of superior cold flow or higher stressed engines.

That said, my research into late model GM requirements found that the Dexos specification is so tightly written that any oil meeting the spec is essentially identical for all practical purposes.

If anyone has a different source of information I’m always interested in learning of it.
 

sealandsky

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Got this truck (around Oct 2020) and it's been great. 104k when I got it, it's like 107k now. Oil life is around 55%.

At what oil percentage do you guys usually change the oil? I'm going to do it myself and was thinking about changing over to full synthetic Mobil 1(I'm sure it has the regular conventional oil in it for the last 107k miles). The car doesn't drive much so I figure the synthetic is better for this situation. Used to be a rental truck now it's in retirement, haha.

I also read some people say it's bad to switch to synthetic after a long use on conventional, but then I see tons of videos saying there is no issue.

Anyone switch to synthetic after a LONG time on conventional?

Also, will the OLM know somehow that the oil is synthetic and will keep the percentage higher than if it was on conventional? I'm not sure how that works.
I never let mine get below 50% and also use Mobile 1 full synthetic 0-20.
 

hcvone

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I like my Callaway brother above I use Mobil 1 full synthetic 0-20, that's what Callaway wants for warranty so that's what I use, even though I have used and sold Amsoil since the 80's, yea I am OLD. My dealership seems to change it often, with free oil changes, I don't care if thay change it weekly, they even come get the truck from my house, probably just want to drive it. ;)
 

iamdub

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I've had this one for about 10k miles

Needa 653096US M12-1.75 Oil Drain Plugs and Gasket for GM https://smile.amazon.com/dp/B001NYM...abc_KJQSK327DAACQWZ35QDW?_encoding=UTF8&psc=1


Thanks for this- I saved it in my cart, to be confirmed later. I've always wanted to switch to a magnetic plug but never remember to get one before my annual oil change. I'm not even sure if my pan has the original thread size since it has been Helicoiled. I should've replaced the pan when I had the motor out.
 

iamdub

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Got this truck (around Oct 2020) and it's been great. 104k when I got it, it's like 107k now. Oil life is around 55%.

At what oil percentage do you guys usually change the oil? I'm going to do it myself and was thinking about changing over to full synthetic Mobil 1(I'm sure it has the regular conventional oil in it for the last 107k miles). The car doesn't drive much so I figure the synthetic is better for this situation. Used to be a rental truck now it's in retirement, haha.

I also read some people say it's bad to switch to synthetic after a long use on conventional, but then I see tons of videos saying there is no issue.

Anyone switch to synthetic after a LONG time on conventional?

Also, will the OLM know somehow that the oil is synthetic and will keep the percentage higher than if it was on conventional? I'm not sure how that works.


I agree with @Bill 1960. I ignore the OLM and run full-synthetic and change it when it starts to get too dirty for my liking, which is around 5,000 miles. The oil and its additives are still good at this point, but it still has contaminants that I want out, and that's the purpose of the oil change. 5K miles is convenient because it's a good OCI as well as a good tire rotation schedule. Lift the vehicle once and do all of it while it's in the air. Rotating the tires, inspecting and cleaning the brakes (blowing them out with air compressor), checking air pressures, etc. give the oil extra time to drain thoroughly.

The OLM uses engine run time, idle time, operating temperatures, engine loads, and other factors to calculate the oil life. It doesn't analyze the oil to determine its type or level of contamination. The 3K mile OCI is a VERY outdated suggestion. Modern quality conventional oils, when paired with a quality filter, are easily good for 5K miles and more. But, a quality full-synthetic oil will be in much better condition at those same given mileages.
 

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