Going through our yearly maintenance on all our trucks and equipment, and with oil getting expensive/hard to find its got me thinking. I have a combine, dump truck, skid steer, and some other items that add up to about 20 gallons of oil. Most of these engines are only seeing 50-60 hours a year on them, and parked in a barn year round. When they are ran they are getting worked pretty hard so i'm confident any condensation is getting burnt off. I know the general consensus is to change oil every 12 months but is that really necessary in our case?
Running engine oil for longer than 12 months?
- Thread starter JD3020
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12 months has always seemed arbitrary to me. Were it my money I’d test it, could potentially have lots of life left
Oil doesn't go bad sitting in an engine. Base your oil changes on actual hours of run time and not months since the last change.
Sounds like you could more than likely go 18 months. I probably would.
But... it does. It is exposed to moisture. And acid byproducts. And fuel and other contaminants. In a bottle on the shelf, it's probably good for 20-30 years in ideal conditions. In an engine, exposed to lots of elements and environment, maybe a year.
How many hours do the service manuals say? I'd go to however many hours is specified in the service manual, but also remember oil is cheap insurance and heavy equipment is not cheap to replace.
This ^^^^^^^^^^^
I would also add that it depends on where you live. When I lived in the Midwest, the oil in my engines were exposed to very high humidity, and large temperature swings. Especially during Spring and Fall. High dewpoints accompanied with barely above freezing temperatures added to condensation accumulating in the oil.
Living in a hot, dry desert environment, with very low humidity is far better on any oil, in most any engine. With that said, I wouldn't leave oil in anything for over a year. As was mentioned, you can't get away from fuel and acid contamination. All engines produce them.
If I was going to push motor oil, the best candidate for the job would be a smaller engine that runs on propane.
If the engines get a good hard run once in a while, that will burn off any condensation that may accue in the oil. I have a barn kept 1940 Ford tractor that gets 3 hard two hour runs per year. I have always done five year oil/filter changes on it. Been doing that for 35 years now.
This is a common misconception. Acid byproducts are the result of combustion so if there is no combustion then acids are already neutralized by the buffers in the oil. Oil does not become more acidic just sitting in the oil pan. The vast majority of water also comes from combustion. As long as the TBN is not depleted then the oil will not become more acidic during non-operation.
^^^^WOW MAN WRONG FORUM^^^^^
Why are you not on the sales section here? I'm sure for what you need volume wise there is some GREAT deals out there. Chevron makes good HD type oil and constantly has rebates etc.
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Yes they do but during operation and it is dependent on the amount of sulfur complexes in the gasoline. Acids aren't being produced if the engine is not operating. With low sulfur fuels these days the necessity of the oil to resist acid contamination is greatly reduced.
This is where Oil testing REALLY pays, when you have 20 gallons not 1
As someone suggested have it tested and go from there.
I think we are upto 2 years in the equinox. Need to kidnap it for a day and get that changed out.
It did leak or use about 1.5quarts in 2000 miles so it has been freshened.
Car only gets about 1000-2000 miles per year on it.. needs a new battery too.
Its the org. from 2012.
It did leak or use about 1.5quarts in 2000 miles so it has been freshened.
Car only gets about 1000-2000 miles per year on it.. needs a new battery too.
Its the org. from 2012.
But they are when it is. Do they secretly go away when the engine is shut off? Then mysteriously reappear when it is started again?
No they get neutralized by the alkaline buffers in the oil. The remaining TBN (B=base=alkaline) gives an indication how much of this neutralizing ability remains.
It's not a secret it's chemistry. As the engine operates the sulfur compounds in the fuel are oxidized and as this combines with water from the products of combustion it produces acid. But this is neutralized up and until the buffering ability of the oil has been exceeded. It's a bit more complicated than that but this is a basic summary. The point being the bad actors aren't secretly generated just sitting in the pan.
My car was on a 2 year or 22k miles service plan from the start. BUT if i do less than 6000 miles the oil should be changed yearly.
They seem to be concerned about short tripping, or the C2 oil's ability to deal with it.
They seem to be concerned about short tripping, or the C2 oil's ability to deal with it.
Just changed oil in my 2300 after about 31 months, about 7K miles (syn). Basically a short tripper for about 1/2 that time. Didn't sweat it a bit.
I used to adhere to the 1 year rule; I don't bother anymore. Fuel control on modern vehicles is excellent; YMMV
I used to adhere to the 1 year rule; I don't bother anymore. Fuel control on modern vehicles is excellent; YMMV
I would love to start oil sampling stuff but for me its just a matter of not having time or the organization to pull samples and get them sent out. Between my equipment, my grandparents farm equipment, and our fleet equipment i'm doing maintenance on 9 trucks/suv's, 6 tractors, 2 dump trucks, 4 skid steers/excavators, and a bunch of small engines/trailers/etc.. over 3 locations. I'm struggling as it is to keep up with everything while working/farming, and thinking about sampling oil gives me a minor panic attack.
As for the factory intervals it varies, one truck is a '86 F-350 dump truck with a 460 that i run 15w-40 in. It gets maybe 1k miles a year on it, and i'd imagine the book says around 3500. Also have a newer skid steer and a mini-ex that i run 5w-40 in and get about 50 hours a year, i think they say 250-350 hour services. I think the Deutz in my combine is 150/hr interval and i put 35 hours on it last fall. So i'd say on average we're around 1/3 of what the books call for on oil changes.
As for the factory intervals it varies, one truck is a '86 F-350 dump truck with a 460 that i run 15w-40 in. It gets maybe 1k miles a year on it, and i'd imagine the book says around 3500. Also have a newer skid steer and a mini-ex that i run 5w-40 in and get about 50 hours a year, i think they say 250-350 hour services. I think the Deutz in my combine is 150/hr interval and i put 35 hours on it last fall. So i'd say on average we're around 1/3 of what the books call for on oil changes.
The samples I sent out from my rarely used Peterbilt showed the oil to be perfectly serviceable after 3 years.
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