Oil: I'm Not Convinced It Ever Needs To Be Changed

[troutsqueezer]

OK, of course it does but.... enter Pete, my neighbor who is 75 years old, lives by himself on the parcel next to mine. He speaks mostly Italian. Almost 30 years ago he bought a well-used Kubota, I forget the model number but it is good-sized, maybe 30 hp, with a 72 inch Top and Tilt BB with loader and for the last 25 years he has been taking care of the three miles of gravel road that leads into our little valley here. Three years ago I offered to buy his tractor and take over the maintenance of the road. Together we stood over the tractor, beers in hand, and he gave me the rundown. This was my first up-close look at it and I was taken back by the amount of rusting around the engine canopy, the dash board and the frame in general. He pulled up the canopy and I could see the battery was being held in place by some rusting baling wire. Still, I was seriously considering buying the thing, knowing nothing about tractors, I figured re-working this Kubota might be a good way to familiarize myself with the hardware. Then I asked him when he last changed the oil. Answer: Never. He didn't buy into the theory that it should be changed every now and then. At that point, my mind began to change so I opted out (later bought a B21).
He started it up for me. It ran very well. It did not smoke. He still uses it to this day, on the same oil.

Are we being fooled into thinking that frequent oil changes are absolutely necessary? There is some misinformation being published out there by companies like Jiffy Lube who would like everyone to think they should change their car oil every 3k miles when the manufacturer says every 5 to 6k miles is acceptable. And I'm sure there are tests that exist that demonstrate how old oil becomes less effective in protecting your engine but out here in the real world, at what point does that translate into actual engine breakdown or loss of compression?

I'm not taking the stance of never changing my tractor's oil, but there's a 30 year old Kubota down there in the valley, scraping gravel, pushing rocks and tree limbs. Probably still using that original Flying A oil. :confused2:

 

[MoKelly]

Do you really believe the oil hasn't been changed in 30 years? Really?

MoKelly

 

[Rock knocker]

Would you use similar logic to deduce from the fact that because Keith Richards will soon be 70 and the Jim Fixx died at age 52, that smoking, drinking, drug abuse and herion addiction is healthier than regular exerecise?

 

[greasemonkeyok]

After thirty years I would be afraid to change the oil. Introducing new detergent might cause all the seals and gaskets to leak.

 

[94BULLITT]

Pull the valve cover or oil pan off it, you will see why you need to change your oil.

 

[Baby Grand]

Would you use similar logic to deduce from the fact that because Keith Richards will soon be 70 and the Jim Fixx died at age 52, that smoking, drinking, drug abuse and herion addiction is healthier than regular exerecise?

It is tempting. I do miss smoking. Oh, those tubes of delight.

I worked with a guy who had a Chevy Citation with 70k on it that he bought new. He swore he never changed the oil.
Always suspected he was just pulling my leg, but he was kind of an eccentric, so you never know.

Are we being fooled into thinking that frequent oil changes are absolutely necessary? There is some misinformation being published out there by companies like Jiffy Lube who would like everyone to think they should change their car oil every 3k miles when the manufacturer says every 5 to 6k miles is acceptable. And I'm sure there are tests that exist that demonstrate how old oil becomes less effective in protecting your engine but out here in the real world, at what point does that translate into actual engine breakdown or loss of compression?

I'm not taking the stance of never changing my tractor's oil, but there's a 30 year old Kubota down there in the valley, scraping gravel, pushing rocks and tree limbs. Probably still using that original Flying A oil. :confused2:

It's a tough call - I suspect the vehicle manufacturer is the best source of information as they have to back up what they sell with warranty repairs if it doesn't last. Knowing how black my Kubota's oil gets in just 50 to 100 hrs makes me think that gas car logic may not apply seemlessly to diesel tractor situations.

 

[Ed of all trades]

When I was a teen I was told "oil does not go bad, just dirty." I had a 1974 GMC with a 350 in it that had about 50000 mi on it. I changed the filter many times but only changed the oil one time and it was still running strong at 150000 mi when I sold it. The time I changed the oil was because I got behind on filter change. Does oil go bad? I don't think so but I change the oil in my stuff just like everyone now.:2cents:

 

[ray66v]

Theoretically oil would not need to be changed, if you: (a). Could keep it clean, and (b). Could keep from overheating it.

There are however other other reasons to change oil, such as; acids developing, moisture, and additives wearing out.

My mom has a North Star V8, which from the day it was made, uses a quart of oil every 500 miles, (GM said that is acceptable). At that rate of replenishment, I suppose you could consider it a continuous oil change. :confused3:

 

[sandman2234]

When I was a teen I was told "oil does not go bad, just dirty." I had a 1974 GMC with a 350 in it that had about 50000 mi on it. I changed the filter many times but only changed the oil one time and it was still running strong at 150000 mi when I sold it. The time I changed the oil was because I got behind on filter change. Does oil go bad? I don't think so but I change the oil in my stuff just like everyone now.:2cents:

Back in 1975 that same question about "does oil go bad" was asked by auto mechanic's instructor to an oil company engineer that visited our college for some reason or other. As it turns out (per his opinion) is that oil actually gets better, as long as certain aspects are met. (kept clean, not overheated, etc). During World War II, a lot of oil was saved by simply changing the filter and topping off the level. Since total hours were suspect, with bullets being shot at it regularly, I am not so sure that extended life of the motor was really the main objective in changing the oil, (or just the filter).
I tend to just change the oil, rather than trying to keep it clean by changing the oil filter weekly. My wife's car has a recommended service interval of 5,000 miles instead of the typical 7-7500 miles. It is dropped to that lower number ONLY for the 2.0t motor. (turbo 5,000 versus naturally aspirated at 7,500)
David from jax

 

[MrWhippy]

I know a guy who has an old Land Rover, late 1960s. He decided to see how long the engine would last with just topping up the oil. He drove it over 50,000 miles, just topping off the oil. The engine never actually died. The oil leaks got worse (more than the typical British car) and it eventually began to smoke, mostly from worn valve guides.