The motor oil bottles didnt print the mfg date and exp date...but do they really have a shelf life ?

Would you use the oil that has been sit in the garage for 1+ year ?

what about other fluids ? (transmission, differential...etc)

 

Chemicals do degrade, but considering that they last for years in a landfill, I can imagine they last for years sealed in a container...

 

I have been reading about a lot of people who stockpile the sometimes hard to find German Castrol 0W30. There use to be a green-colored version and many bought that up before the gold version came out not too long ago. Yet people still say the old stockpiled stuff works just as if they had picked it up the same day at a store

 

agreed

 

Base oil, which makes up ~85% of PCMO, last indefinitely. That is the part that is recycled and re-used for produce cheap bulk oil at Jiffy Lube and some dealerships.
Additives may fall out, if left unopened, oil can last 5-10 years, according to major oil companies.

 

I found this on www.carbible.com

Engine Oil Shelf Life

I couldn't decide whether to put this in the FAQ or the main page, so it's in both, because I get asked this question a lot. Typically, the question is along the lines of "GenericAutoSuperStore are having a sale on WickedlySlippy Brand synthetic oil. If I buy it now, how long can I keep if before I use it?"
In general, liquid lubricants (ie. oils, not greases) will remain intact for a number of years. The main factor affecting the life of the oil is the storage condition for the products. Exposure to extreme temperature changes, and moisture will reduce the shelf life of the lubricants. ie. don't leave in the sun with the lid off. Best to keep them sealed and unopened.

Technically, engine oils have shelf lives of four to five years. However, as years pass, unused engine oils can become obsolete and fail to meet the technical requirements of current engines. The specs get updated regularly based on new scientific testing procedures and engine requirements. But this is only really a concern if you've bought a brand new car but have engine oil you bought for the previous car. An oil that is a number of years old might not be formulated to meet the requirements set for your newer engine.

If your unopened containers of engine oil are more than three years old, read the labels to make sure they meet the latest industry standards. If they do meet the current standards, you might want to take the extra precaution of obtaining oil analysis before using them. An oil analysis will check for key properties of the oil and ensure that it still meets the original manufacturing specs. Of course the cost of getting an analysis done on old oil is probably going to outweigh going and buying fresh stuff. So it's a double-edged sword.
As a general rule, the simpler the oil formulation, the longer the shelf life. The following is a guideline under protected conditions:

Product Shelf Life
Base Oils, Process Oils 3 years
Hydraulic Oils, Compressor Oils, General Purpose Lubricating Oils 2 years
Engine Oils and Transmission Oils 3 years
Industrial and Automotive Gear Oils 2 years
Metal Working and Cutting Oils 1 year

The following are signs of storage instability in a lubricant:

Settling out of the additives as a gel or sticky liquid
Floc or haze
Precipitates/solid material
Colour change or haziness
Water contamination in a lubricant can be detected by a "milky" appearance of the product.

 

thanks for the info!

very well explained!

 

most fluids (oil, tranny, diff): a couple of years as stated above.

brake fluid: definately NOT if the bottle is open. I wouldn't use it past 6-12 months depedning on the climate. Brake fluid is hydrophilic meaning it likes to absord water molecules thus rendering the fluid not as efficient as it would be new.

steviej

 

I would look at the back for the API standards. I would only use SL or SM rated oils.

 

First API standards are performance standard, they are not measurements of shelf life. Second, API standard printed on the bottles were the one that was tested at the time of the formulation. If the same oil is tested with a newer standard, it will likely to pass. In fact, Mobil 1 SL oil have beefier additive package and better base oil than some of Mobil 1's SM rated oil. German Castrol is a SL oil but has lower engine wears than M1 SM, according to an used oil analysis.

 

Yep, I know API are performance standards. All I am saying is that because of performance I would not put a oil sitting on the shelf for 5 years with a SJ rating in my car. I would rather put something more current like SL or SM. I also understand that the additive package in the SL oils is beefier and the ZDDP has been reduced in the SM oils due to catalytic converter issues.