I'm running approximately 15 year old conventional Citgo Supergard 10w40 in my '16 Versa. It just hit 30K miles and I did a transmission fluid drain/fill/filters. It will be due for an OC in about 1K miles and was wondering if since I have a few jugs of 15 year old 10w30 Pennzoil Platinum in the garage whether the members of the forum thought it would be beneficial to run synthetic oil for one OCI to help clean the engine then go back to the conventional or would you just continue to run the conventional? I know synthetic is supposed to be better oil but I've got probably around 8-10 cases of conventional that needs to be used up so I can't afford to just let it sit and switch to synthetic full time. I've ran conventional 10w40 for 45 years without any issues. Will the synthetic actually do any more cleaning than the conventional? I don't know much about oil technology thus the reason for the question.
Synthetic For Engine Cleaning
- Thread starter FordMan59
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If changed at a reasonable oci, the conventional should be fine.
No. Engine oil is not a cleaning solvent.
Does that 15 years old oil meet required spec on your car?
Seems to me like if you used an in-spec oil and changed on a reasonable OCI, that you would have no reason to fear crud buildup in only 30k. Not on a modern EFI setup. I wouldn’t think of worrying about this.
Seems to me like if you used an in-spec oil and changed on a reasonable OCI, that you would have no reason to fear crud buildup in only 30k. Not on a modern EFI setup. I wouldn’t think of worrying about this.
You can always sell off the conventional oil but a Versa isn't too critical over that. I'd be way more concerned about the CVT transmission.
https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-fs-0w-40/
I can attest to the cleaning power of Mobil 1 oils seen during a tear down.
Then what's the job of all the detergents in these oils?
I should toss that in my 99 and test that claim! It needs a new valve cover gasket and isn’t far from a TB job.
4WD
$50 site donor 2025
You can’t be serious ?
That, and mobil used to specifically state that the mobil 1 high mileage was intended to clean. I don't know if they still state that.
EDIT; Looks like they still state it.
https://www.mobil.com/en/lubricants...products/products/mobil-1-high-mileage-5w-30/
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If you use a quality oil and change at a reasonable interval , you won't need a flush either.
Personally, I'd not recommend flush either as there are risks of sludge chunks plugging some passages.
Oil meant for diesel engines and suitable for gas engines is what I'd use for a couple of shorter OCIs.
Oil meant for diesel engines and suitable for gas engines is what I'd use for a couple of shorter OCIs.
15-year old oil is from about 2005, which means it should be SM-spec. So it is a ‘modern’ conventional oil that will have good quality group-II base oils and a strong add-pack.
At reasonable intervals, it should keep an engine perfectly clean without issue.
At reasonable intervals, it should keep an engine perfectly clean without issue.
With one OCI? You agree that Mobil 1 will clean a 'dirty' engine by using it once?
To not sludge it up in the first place and to keep it clean during the life of the engine, not not clean out a dirty engine with one use.
Marketing. Good luck proving it.
look at the 15 year old XOM internal powerpoint slide i posted
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