GM dealer filled oil with conventional 5W30 vs synthetic, should i worry?

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ok so i have a 2007 cadillac escalade with 215,000 miles on it. It has the factory 6.2L engine. for all of its life ive been filling with synthetic 5w30 when i goto the dealer. this time the guy asked what i wanted and i said synthetic but then he went on break and i guess the other guy followed the computer and apparently it said conventional/reg 5w30 was fine? i thought gm dealers/cadillac dealers always tried to push the 5w30 dexos but thats besides the point. so i have read many threads and it seems like conventional and synthetic perform basically the same and the only reason to run synthetic is for longer oci's. I never really cared for higher OCI's, i just follow the OLM. However I just want to ensure that this conventional fill wont affect anything? like i also heard that if you run conventional all the time then switch to synthetic late in the vehicles life you can run into leak issues. my truck is pretty high mileage so i just wanna ensure that its okay for this oil change to be with the reg 5w30 even tho ive ran synthetic all its life. the main thing that bums me out is that its gonna start getting cold here as cold as -40fahrenheit and i kinda wanted the synthetic for better cold startups, not sure if there will be a big diff between conventional and that for cold temps. i expect the temps to be between -4f and -22f mostly this winter and could get colder to -40 for a day or 2


so my main question is, should i drain the conventional asap and fill some store bought 5w30 or is it fine to keep the reg 5w30 for this oil interval even tho my truck is high mileage and always ran synthetic. i just dont want any problems like leaks or other problems etc

btw i dont even know what oil they ran, it just says reg 5w30 but its a cadillac/gm dealerhsip any ideas? seems to be from the pump machine rather then jugs
thanks!
 
You will be fine.

The oil is still rated to 5W-X for winter starting, and even a base conventional oil will be rated API SN at a minimum.

If you are worried, just change the oil a bit early, say 50% OLM, but I wouldn’t drain out fresh good oil.
 
You will be fine.

The oil is still rated to 5W-X for winter starting, and even a base conventional oil will be rated API SN at a minimum.

If you are worried, just change the oil a bit early, say 50% OLM, but I wouldn’t drain out fresh good oil.

yeah i assumed it was okay! thanks for the reply! u think the cold flow for this oil compared to a syn will be negligble? or is it a pretty big diff

thx
 
You will be fine.

The oil is still rated to 5W-X for winter starting, and even a base conventional oil will be rated API SN at a minimum.

If you are worried, just change the oil a bit early, say 50% OLM, but I wouldn’t drain out fresh good oil.

100%
 
You’ll be fine but if you paid for synthetic then you get some money back or your oil changed over to synthetic.

nah they ended up charging me for reg, and at the desk she said sorry we went by the computer it said reg for yout truck. i was certian my truck said syn but whatebver
 
I agree that conventional oil will be fine. In 45 years of driving I've never used a drop of synthetic oil and currently run 5K-7.5K OCI's. I ran an '88 Escort to 518K miles on conventional. If you're really worried about it take it back to the dealer and tell them you requested synthetic. You should be able to get it done by paying the difference in price between the conventional and the synthetic. If they refuse to make it right start taking it somewhere else for oil changes, other maintenance, and repairs.
 
nah they ended up charging me for reg, and at the desk she said sorry we went by the computer it said reg for yout truck. i was certian my truck said syn but whatebver
Well that’s good. As long as they used a quality conventional that meets the specs needed for the engine, you’ll be fine.
 
u think the cold flow for this oil compared to a syn will be negligble? or is it a pretty big diff
A 5W-30 mineral oil and a 5W-30 synthetic oil both need to pass the same 5W cold pumping test. Note the “W” stands for winter (not weight) and is a measure of its cold weather performance.
 
You'll find that most 5w-30 available that meet modern specs (SN+, Dexos 1G2, etc.) are really a synthetic blend, even if the bottle doesn't advertise it as such. You're not hurting anything by running the conventional 5w-30 for one interval. Sure, the top-tier synthetics probably offer tangible benefits in cold start performance and endurance, but it's not worth wasting good oil over IMO.
 
thanks for the replies! i guess its gonna stay in

any ideas on waht they used? receipt says reg 5w30 i saw it come out of the pump thing rather then jugs
 
Conventional 5w30 is fine for your 2007 Escalade. The dexos requirement started with 2011. Your OLM assumes the cheapest API SM conventional. SN and SP are much better than any SM, and even "conventional" is a syn blend now, anyway.

Dealers mostly use random bulk oil
 
thanks for the replies! i guess its gonna stay in

any ideas on waht they used? receipt says reg 5w30 i saw it come out of the pump thing rather then jugs

based on my experience with a few different dealers, jugs are typically in parts dept. for sale. The service dept. uses bulk oil from the pump.
 
Rather than go through the hassle of fighting with them, as long as I paid for the conventional oil, I'd shorten the OCI. Then add it to the long list of reasons for why I do my own work, after kicking myself for taking it to the dealer.
 
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Rather than go through the hassle of fighting with them, as long as I paid for the conventional oil, I'd shorten the OCI. Then add it to the long list of reasons for why I do my own work, after kicking myself for taking it to the dealer.
Seems like us “spring chickens” are up late in the work week for some reason 😷
 
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