Does Motor Oil Go Bad?

[Black_Sheep]

Properly stored oil, not an issue. In the crankcase is another story. Oxidation of the oil and contamination from condensation and combustion by-products cause acids to develop in the engine oil.

 

[moparwacko]

On the opposite end of the spectrum-

My last work truck was a new 2017 Ram 5.7 Hemi Quad cab 4x4. It was fleet maintained and got it's oil changed once a year. I drove it for 4 years for a total of 361K. I asked the fleet manager why don't you change it sooner? His answer was $$$, and we just don't see any oil related engine failures. That truck was still running like new and still didn't leak or burn any oil. They used Pennzoil Synthetic Ultra Platinum.
Amazing engine.

 

[WileE]

I give you guys a good, TRUE story. Back in the day, we're hanging out on the street, guys talkin' cars. etc. So, we're discussing oil & filters, and a neighbor older guy (like WE are now) passes by and joins the younger crowd in our chat. He was "sorta" a car guy, he liked us guys with the performance cars. We ask him how often he does an oil/filter change in his 1965 (?) Olds Dynamic 88. He says, "change the oil ? Never. I just add some when it gets low." It was over 5 years he bought the car ! I'll never forget that.

 

[68BabyBlue]

I give you guys a good, TRUE story. Back in the day, we're hanging out on the street, guys talkin' cars. etc. So, we're discussing oil & filters, and a neighbor older guy (like WE are now) passes by and joins the younger crowd in our chat. He was "sorta" a car guy, he liked us guys with the performance cars. We ask him how often he does an oil/filter change in his 1965 (?) Olds Dynamic 88. He says, "change the oil ? Never. I just add some when it gets low." It was over 5 years he bought the car ! I'll never forget that.

I have a similar one. Wife’s kid sister bought her first car, a new Toyota Celica, in the late 80s. After 110000 miles the engine locked. She never checked or changed oil.

 

[sam dupont]

My Dad told me, somebody, I think it was Kaiser, offered a "sealed" motor that never needed oil... For a very short time.

 

[maxwedgechar]

When Max was in the shop in 2018 I had the 4.88s swapped out for 4.11s. I had my friend use AMC Limited Slip oil from cans that were probably 50 years old that I'd had since 1984. Same thing when he did the axle bearings on the B350. No issues. I told him I wanted the empty cans back and I sold them at Hershey that year. I think I got $5 a piece for them!

 

[Longram330]

Funny thing, I just stumbled across this "oil age" business. I ended up getting a few gallons of brand new oil (John Deere 50-II ) , on the back panel of the container right under where all of the API and SAE standards are listed, it states that the oil has a five year shelf life! First time I've ever seen this on an oil container!

 

[Dibbons]

And how long was petroleum in the ground before being bottled (LOL)?

 

[sam dupont]

Although I have worked in refineries, I have never been around the drilling. I've been told that it sometimes comes out of the ground as though it had been separated. I haven't seen it firsthand, but I've been told that sometimes it comes out just like the oil we put in our engines. I know there's a waste product at the drill sites that's so similar to pump gas, a friend of mine runs his slant six pickup on it.

 

[bobfake]

Interesting discussion…this prompts a question. I am using a high zinc oil in my stock 383 Super Bee. Can I safely switch to a synthetic oil? Is there a high zinc synthetic available?

 

[tonysrt]

I bought PennGrade 10-40 partial synthetic with high levels of zinc & phosphorus says the hi levels protect flat tappet or roller lifters. I haven't used it yet.

 

[Kern Dog]

On the opposite end of the spectrum-

My last work truck was a new 2017 Ram 5.7 Hemi Quad cab 4x4. It was fleet maintained and got it's oil changed once a year. I drove it for 4 years for a total of 361K. I asked the fleet manager why don't you change it sooner? His answer was $$$, and we just don't see any oil related engine failures. That truck was still running like new and still didn't leak or burn any oil. They used Pennzoil Synthetic Ultra Platinum.
Amazing engine.

Your boss approved oil changes based on 90,000 mile intervals?

 

[moparwacko]

Your boss approved oil changes based on 90,000 mile intervals?

You have to understand large corporations. My direct Supervisor was an ex submarine captain who knew absolutely nothing in our line of work. He really had zero influence over the transportation department.
It was the "Transportation Department" who actually owned the vehicles. They set the maintenance schedules, repaired anything, and so on. It mattered not what I or the Sub guy thought about it.

 

[Triplegreen500]

Oil just "sitting" in an engine, absorbs environmentals - humidity, dust, pollutants. These are not sealed systems, they breathe.

I have air-cooled motorcycles. If you don't run the engine up to operating temperature, and keep it there long enough, the oil turns into a "milkshake".

This, is what happens when you don't get the oil hot enough to burn off the condensation/moisture. And, that IS synthetic. The air itself may not have a lot of condensation in it, but think about a cold soda can on a hot, humid day - it DRIPS. Well...so does the inside of an engine block - and it all mixes with your oil.

Lots of people assume this inside your oil cap

means you have a blown headgasket, in a liquid cooled engine. Not necessarily - it's condensation in the oil. Granted, liquid cooled engines are thermostatically temperature-regulated (unlike air cooled engines), so they do get up to temperature much more quickly...but it still happens.

Oil is cheap (especially compared to hard parts, and labor).

And, just like that gallon of milk in your fridge...eventually, it will go bad.

Yes, petroleum was "in the earth" for millions of years...unrefined. You don't want to run that through your engine. And, refined oil? Will RETURN to an un-refined state as it sits - it will lose its refined properties, and "spoil". You can still use it for chainsaw chain lube...but I wouldn't want to run it in my Hemi.

Oil's cheap. Change it at least once a year (6 mos is manufacturer recommendation). If nothing else, it's a chance to have hands and eyes on your car once a season to make sure you don't have REAL problems going on.

 

[Cranky]

To maintain the factory warranty on my HellCat, I do the oil changes every 6 months as required by the manufacturer….

There's wording in the paper work that you have to have the oil changed every 6 months and is dictated that a dealer service center has to do it? I've been down that road before and do my own changes and never had to prove it.

 

[Triplegreen500]

No location requirement; worst case, keep your receipts and note date/miles so you can prove diligence if there's an internal engine failure.

 

[Ultra mag]

After 4 months it tastes funny and will give you the farts

It gives me the greasy shits.

 

[Cranky]

Although I have worked in refineries, I have never been around the drilling. I've been told that it sometimes comes out of the ground as though it had been separated. I haven't seen it firsthand, but I've been told that sometimes it comes out just like the oil we put in our engines. I know there's a waste product at the drill sites that's so similar to pump gas, a friend of mine runs his slant six pickup on it.

Even though I was a machinist in a refinery for 26 years, it wasn't hard to learn about oils and oil blending. Out of the ground you have sweet and sour crude. The refinery I worked in was a sour crude plant and some of it came in with lots of crud in it including sand. Had one storage tank that got a pretty bad load and the thing was 1/3rd of the way full of crap. Every tank needs to be turned around from time to time but this one needed it badly lol. Really nice sweet crude is....well, pretty nice stuff.

As for shelf life....there's some oils on my shelf that's several years old and so far so good. Always check it before pouring it in to make sure none of the additives have settled to the bottom. If so, shake it up good. Some additives will settle while others do not. As for moisture....never seen any in a full bottle that was sealed and never noticed any in one that was half full either.

 

[RemCharger]

I remembered Project Farm guy tested 70 year old oil...

The guy reminds me of Steve Carell on the anchorman, and he has to take a ****

Good video though.

 

[oldkimmer]

I worked at a dealership in the mid 80s. A van came in on trade. The shop Forman tells me to give it an oil change. The now X owner said: u can if u want, I never have. I had to poke a screw driver in thru the oil plug hole to get the oil to kinda drain out. Pulled the pan off and the sludge in the bottom of the pan was an inch thick. Kim