Engine oil

MJWB

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I have some new unopened engine oil bottles on board. 15W-40. Bottles date stamped 9/2017. Any views on what the shelf life might be please? Thanks.
 

VicS

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Never understood shelf life on bottled spring water ,, been underground for years . Why would it go off in a bottle
Leaching chemicals from plastic bottles.

A few years ago I posted a link to a paper published in one of the scientific journals but cannot begin to find it now.
 

vyv_cox

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Probably about a1,000 years depending on storage conditions?
I am not joking.
Awaiting the scientists.............
Modern lubricants may include 25% additives. The distilled hydrocarbon content may not deteriorate in storage, although there may well be some changes due to the formation of asphaltenes. But there will certainly be some interaction between, and degradation of, the additives. The oil may run in the engine but wear will accelerate and it may foam, with negative effects on the bearings.
 

Seashoreman

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Modern lubricants may include 25% additives. The distilled hydrocarbon content may not deteriorate in storage, although there may well be some changes due to the formation of asphaltenes. But there will certainly be some interaction between, and degradation of, the additives. The oil may run in the engine but wear will accelerate and it may foam, with negative effects on the bearings.
vyv, are there many additives in 15/40 oil? I always thought it was basic 'van oil'? Basic natural?
Please elaborate, with respect.
 

vyv_cox

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vyv, are there many additives in 15/40 oil? I always thought it was basic 'van oil'? Basic natural?
Please elaborate, with respect.
All lubricants contain additives. Cheap oil blenders will buy in a complete package from an additive supplier, major names will use some of their own plus components from commercial suppliers.

At the very least the package will include anti-oxidant, boundary lubricant (for cams and tappets), VI improvers, etc. This link elaborates Types of Lubricant Additives - About Tribology

The lowest additive content oils that I am aware of are machinery oils where combustion is not involved, such as Shell Turbo T. Additives in these oils amount to 2 - 3%, anti oxidant and anti corrosion.
 
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