Sealed Motor Oil, How Old is Too Old to Use?

[PDJetta]

I changed the oil in the lawnmower today and I found an unopened quart of 30 weight (detergent) Trak Auto (Trak is now out of business!) brand oil in my garage. Its "SJ" rated, if that gives any indication as to its age (I have no idea what rating the gasser oils are up to now). I suspect it is between 10 and 17 years old.

Anyway, I used it when I changed the oil in the mower. I suspect its OK to use. Any thoughts?

Tx.

--Nate

 

[dieseldorf]

it's good for a couple of years.

 

[speed185187]

it's been sitting in the earth for millions of years before we discovered it

 

[dieseldorf]

Shelf Life of Unopened Mobil 1 QuartsDoes Mobil 1 synthetic motor oil (in an unopened quart) have any sort of shelf life, like conventional motor oil? -- John Lantz, Littleton, CO



Answer: ExxonMobil recommends a five year maximum shelf-life for engine oils, including Mobil 1.

 

[VFchicago88]

sure companies say that, but any sealed oil that is very old, like this guys, is fine for use in a mower or something like that.

 

[leicaman]

Yes it would be okay for a lawnmower. But with that said, I am one of those who use synthetics on my small engines. They use no oil and the engines last longer than the other parts do.

 

[Pat Dolan]

Motor oil in a sealed, non-UV exposed container could last practically longer than you and I will. There is only a tiny bit of oxygen availbe for degredation and no UV to help that process along.

HOWEVER, some of the additives in motor oils DO precipitate (called "drop-out" in the trade) so the oil will be depleted of some of the constituents that made it meet the service grade, but not the viscosity class (straight 30 does not even HAVE any VIIs).

BTW" it is anything but true that oil was stable in the ground for millions of years. Over time, it actually changes from something else to oil, and eventually from crude to heavier crude, depending on conditions.

 

[PDJetta]

sure companies say that, but any sealed oil that is very old, like this guys, is fine for use in a mower or something like that.

That's what I figured. I Googled on the "API Service Rating History" and SJ came out in 1997 and SL (There was no SK) came out in 2001, so the oil I used is between 11 and 7 years old.

I get about 20 years of use out of a push mower, about the same for my cars! It all comes down to proper maintenance.

--Nate

 

[pete9686]

Proper maintenance and avoiding using it as a roto tiller.

In the last ten years I have ruined a couple of perfectly good mowers by being stupid and running them into something hard and immovable. It doesn't kill them on the spot, but, it generally puts a very small bend in the crank.

In each case, the mower restarted and lasted a few months with a slight vibration. Eventually metal fatigue wins and it dies in spectacular fashion with a bang and a cloud of smoke as the oil comes out the side of the case.

As for it being used, I would guess that it is fine for a mower, especially if you are like me and will kill it in a few years doing something dumb anyway!

 

[PDJetta]

"In the last ten years I have ruined a couple of perfectly good mowers by being stupid and running them into something hard and immovable. It doesn't kill them on the spot, but, it generally puts a very small bend in the crank. "

I had an old push mower once and I hit a stump with it and it vibrated horribly afterwards. I thought the blade was bent, so I bought a new one. Well, when I changed the blade, I noticed the crankshaft was really bent. I thought the mower was history.

Just for the heck of it, I took an 10 pound sledge hammer and gave the end of the crankshaft a couple of calculated smacks and it straightened it right out and I used that mower for 5 years more and then gave it to someone else! I did wonder about metal fatigue, though and occassionally pictured the crank breaking and the flying blade taking my foot off, but it never happened.

--Nate

 

[Gil]

I use the drain oil from my TDI in my lawnmower. It seems to run better and the nice black color makes reading the dip stick easy.

 

[Jetta SS]

A couple years ago I used some montgomery ward 30wt in my mower I bought at an estate sale. it was actually in a can that you had to put the old bladed funnel in to crack it open. it was a cool experience. my guess is it was from the 70s.

 

[bikeprof]

Hmmmm, oil that is in a can that is hermetically sealed shouldn't go "bad".

Since the time period that API gave oil designations to help improve the cleanliness of the motor/engine, and to also help improve mileage(start up and the durability of metals is in here somewhere...), must have been sometime in late 1950's but did not get to the market until early 1960's.
The superceding of an alphabet letter(ie. E over D), does NOT negate the ability of that preceding letter to do its duty, the oil is still useful or can been useful.
Because the quality is a little less, if you have a can of those oils..., they are limited in the "now day" engine use.
That is all!

It is AMAZING the amount of "adjustment" that is done to an oil these days !

PS. the re-cycling of ANY SYNTHETIC oil into any lawnmower is actually a HUGE improvement for that antiquated contraption(the lawnmower), the motor...

 

[yoseppi]

Hmmm, I can't remember the last time I changed the oil in my mower.

But I would agree that it probably would outlast us in a sealed container away from UV. Of course companies that SELL oil would tell you to BUY new.