Does Motor Oil Go Bad?

[Dibbons]

According to this recent MSN internet article it does. I know additives wear out and oil becomes dirty, but if I don't drive the vehicle for six months, I see no reason to change the oil. How is it going to become dirty or contaminated when it's stored?

Should You Get Your Car’s Oil Changed Based on Mileage or Time?

 

[#41]

I thought oil sat dormant in the earth for a million years just to become good?

 

[sam dupont]

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

 

[kiwigtx]

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

Only if you mix it with Coca-Cola.

 

[tonysrt]

And if mixed with Bud Lite really strange things happen.

 

[RemCharger]

In Mexico, no problem. Up north, temp combined with moisture introduces condensation.
Water in the oil, rust on the metal.

 

[66 Sat]

It's a bit misleading - if the car is sitting there doing nothing it's going to be ok for a much longer period than if it's done 100 trips of 1 mile over the last 6 months. That's why they have the mileage/time period, to cover all the drivers who drive to the train station each morning and then home at night and the car barely warms up.

I do agree with RemCharger on the moisture, but I think it's less of an issue than the multiple short trips with very low mileage covered.

 

[Kern Dog]

MSN ??

 

[MiradaMegaCab]

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

 

[maxwedgechar]

My best friend who is a retired Porsche mechanic says you can never change your oil too many times. The oil in my 360 '92 B350 Church Van gets changed about every 1000 miles.

 

[tonysrt]

I always run my SRT till oil temp is above 212* to keep condensation out of the oil. I wish all cars had an oil temp. gauge. And I'm not putting them in myself.

 

[moparwacko]

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

I just go by the expiration date to avoid any gastrointestinal issues.

 

[bearman]

Run a pure synthetic oil and don't worry about. Base oil does wear out after time or mileage. The additive package is what gives up so if you run 5000 miles a year then change it then otherwise don't. If you really want to know what your oil is doing take a oil sample that will tell you when to change it.

 

[WileE]

Condensation absorbsion by the oil is not good.

 

[Dibbons]

I wish all cars had an oil temp. gauge. And I'm not putting them in myself.

When my parents purchased their special order 383 '71 Road Runner when I was a teen, I asked the local mechanic to install a Stewart Warner vacuum gauge and oil temperature gauge in the dash. If I remember correctly, the oil temp took much longer to stabilize (warm up) than the coolant. I believe normally the warmed up to about 240°.

 

[68BabyBlue]

When my parents purchased their special order 383 '71 Road Runner when I was a teen, I asked the local mechanic to install a Stewart Warner vacuum gauge and oil temperature gauge in the dash. If I remember correctly, the oil temp took much longer to stabilize (warm up) than the coolant. I believe normally the warmed up to about 240°.

I had both gauges in my Peterbilt. I wouldn't roll the truck until the oil temperature gauge, which lagged behind the coolant temperature, started to climb. Sill had the original main bearings intact at 1.7 million miles.

 

[SlingLow]

Here in Washington state, I change the oil on my equipment every 100 hours. I write the hours and date on the filter with a sharpie. If I see a date that's 1.5 years old or more I change the oil regardless of the hours. Why? It's a couple gallons of oil and a $12 filter. Cheap and easy compared to any kind of rebuild and it's sat through at least one winter.

Synthetic oil in my cars get changed every 5k miles. Diesel truck at 5,000-7,500 miles depending on how I'm working it. Anything that looks dirty gets changed. I do a lot of oil changes and I actually enjoy it.

 

[68BabyBlue]

Here in Washington state, I change the oil on my equipment every 100 hours. I write the hours and date on the filter with a sharpie. If I see a date that's 1.5 years old or more I change the oil regardless of the hours. Why? It's a couple gallons of oil and a $12 filter. Cheap and easy compared to any kind of rebuild and it's sat through at least one winter.

Synthetic oil in my cars get changed every 5k miles. Diesel truck at 5,000-7,500 miles depending on how I'm working it. Anything that looks dirty gets changed. I do a lot of oil changes and I actually enjoy it.

In my 42 years in the trucking business, the smart money always said that oil is cheaper than engine work.

 

[BeepBeepRR]

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

 

[Darrah]

I wouldn't be concerned running old oil in my cars.

That being said, oil quality, age, and storage is a BIG deal in industrial reliability programs. Lots of money gets invested in having closed storage (preferably climate controlled), outside of sunlight, and rotating drums to use within a certain amount of time. But that's for critical gearboxes that have extreme downtime and repair cost. We also require new oil to run through two filters (10 and 3 micron) as it's added to the gearbox, and do monthly oil analysis. Totally different world than with cars.