Changing oil not Necessary

[user removed]

Reminds me of the article in Mechanics Illustrated (long ago memory could be wrong) where the car owner used a roll of toilet paper for a filter and never changed his oil.
Article was in the early 1970s.

I have recently started going with 10k oil changes and do them myself. I use Mobil 1 and a Fram extended life oil filter. I will never add oil to these vehicles. Both have just over 30k miles and are as clean as new inside.

I had gone from dino to synthetic and was changing at 5k with no oil consumption between changes so I decided to try 10k.

I would rather change the oil than pay for an analysis. Nissan recommends having the CVT fluid analyzed and changed if necessary. I figure I will just have it changed at 60k since the analysis is almost as much as the change.

If you are trying to save 40 quarts in 100k miles by not changing your oil then I guess when you change your engine you will learn a valuable lesson. To me it's cheap insurance.

My used oil is taken to my old shop where they burn it for heat in an EPA approved waste oil heater. Other municipalities collect and use it for generating electricity.

regards
Mech

[Frank Lee]

It depends on the duty cycle. My old commute was on the poor end as it wasn't long enough for thorough warm-up so the naughty stuff didn't get evaporated off. My Mom's commute was absolutely perfect though- about 15 miles of lonely straight level 2 lane one way with only a couple stops the entire trip. The cylinders in her car at 150,000 looked as new- no ridge at all and crosshatching looking fresh. Her car didn't get the "severe service" oil change regimen either. If I had that sort of duty cycle I would change the oil even less often than now. I've only recently put synthetic in one of my vehicles not for any oil longevity reasons but mainly for flow at -40F cold starts. I believe I hurt my '94 way back when it was nearly new with one of those cold starts- ever since there's been a slight lifter tap on cold start.

[euromodder]

Originally Posted by Artan

Mr. Dremd; I regularly check the oil in my car. I put some on my finger and supressit it with other finger. ON the other hand i put the same oil but NEW to check if there is a difference between old and new oil. Absolutely nothing. The viscosity is totally the same.

This is ridiculous, really.
The low temperature viscosity isn't the real issue either, it's the high-temp viscosity you need to know and measure.

If metal particles would be big you would feel it on your finger.

Many vehicles have magnetic oil drain bolts.
They collect a fair bit of metal parts that you can really feel.
Even small metal parts in oil are abrasive when they get in between the surfaces they need to lube. All this junk accumulates over time.

Metals are also an indication of the wear of the engine.

In a diesel, soot also accumulates in the oil.
That's not good either.

I am absolutelly convinced that we never need to change oil in the engine as long as the oil doesnt get contaminated with water, fuel, other external chemicals or contaminants.

Never may be a very bold claim, but oil is often changed far too frequently.

A friend of mine went 90.000km / 56.000 miles on the original (and very expensive) oil in his diesel Beemer.

Many trucking companies run long oil change intervals, with multiple filters, including a low flow, very fine bypass filter to get the smallest particles out.
A car usually has but 1 filter.


Direct contamination with fuel or water will certainly ruin the oil quickly.
Oil dilution has become an issue with more modern diesels with particle filters, or when you're running biodiesel.

The oil in the engine isn't sealed off from the atmosphere, so some water vapour does get in and out with temperature changes.


Remaining TBN is the factor to look for when you want to run your oil for extended periods. It will go down over time, and ultimately will indicate when it's time to get rid of the oil - if it hasn't accumulated so much crud that it needs replacing before the TBN drops too low.

[Thymeclock]

Originally Posted by Old Mechanic

Reminds me of the article in Mechanics Illustrated (long ago memory could be wrong) where the car owner used a roll of toilet paper for a filter and never changed his oil.
Article was in the early 1970s.

I had one of those. The toilet paper was inserted into a heavy aluminum canister that had a threaded fitting. It seemed a good idea, with toilet paper being much cheaper than a new oil filter. It seemed to work OK, but it was much messier to change than an ordinary oil filter. Also you had to unwind some of the toilet paper from the roll to get it to be the right diameter to fit in the canister. Using it eventually became more trouble than it was worth.

If you are trying to save 40 quarts in 100k miles by not changing your oil then I guess when you change your engine you will learn a valuable lesson. To me it's cheap insurance.

I couldn't agree more.

[jkv357]

Originally Posted by Thymeclock

I had one of those. The toilet paper was inserted into a heavy aluminum canister that had a threaded fitting. It seemed a good idea, with toilet paper being much cheaper than a new oil filter. It seemed to work OK, but it was much messier to change than an ordinary oil filter. Also you had to unwind some of the toilet paper from the roll to get it to be the right diameter to fit in the canister. Using it eventually became more trouble than it was worth.



I couldn't agree more.

That's funny stuff!

Toilet paper is made to breakdown. Hot oil moving through it would speed-up the process I would expect. I also would expect an amount of paper fibers to circulate in the engine and eventually wad up somewhere like an oil passage.

Here's some interesting reading for those that think all current oils are the same, that any oil stating the required rating on the bottle has to be fine, and that any brand will do -

The Petroleum Quality Institute of America


Jay

[some_other_dave]

Originally Posted by Artan

Did anybody ever in his life saw a test with two same engines, one changing the oil and the other no?

How do you feel about one engine, changing the oil at a shorter interval and then at a longer interval? With oil analysis done after each of those changes?

That's what I have done in my car. I ran one fill of oil (Mobil 1) for 6,000 miles and had it analyzed when it came out. There were small amounts of wear metals in it; the conclusion was "the engine is a bit tired". I then ran one fill (more Mobil 1) for 12,000 miles. (Sheer stupidity and laziness on my part!!) The analysis on that came back with very high levels of wear metals, on the order of 10x what they had been on the previous fill.

My conclusion: Changing your oil does, in fact, matter. I will never go 12,000 miles between changes again.

-soD

[gone-ot]

...that "toilet-paper" filter unit was made by STILKO™ and I can attest that it 'worked' at keeping the oil "clean" but it didn't do anything for the buildup of acids!

...a USN buddy of mine had one on his Corvair, and yes the oil was aways honey-clear in color, but it also stank like a 100-year old outhouse (sulphur-dioxide)!

[dremd]

Toilet paper (aka cellulose) filters actually do more to prevent acid formation than any other filter.
Cellulose has the ability to suck up lots of water and keep it out of your engine.
Try dropping a roll of TP in the toilet, you will see what I mean.
That said it still has a finite ability to hold water.
Big issue with TP filters is typically that they plug very easily with contaminates vs other bypass filters, that said, filter elements are cheap, very available, and many believe that they filter better than anything.

Again, if you are interested, checkout bobistheoilguy.com forums, tons of very knoleageable people there.

[Thymeclock]

Originally Posted by dremd

Toilet paper (aka cellulose) filters actually do more to prevent acid formation than any other filter.
Cellulose has the ability to suck up lots of water and keep it out of your engine.
Try dropping a roll of TP in the toilet, you will see what I mean.
That said it still has a finite ability to hold water.
Big issue with TP filters is typically that they plug very easily with contaminates vs other bypass filters, that said, filter elements are cheap, very available, and many believe that they filter better than anything.

Again, if you are interested, checkout bobistheoilguy.com forums, tons of very knoleageable people there.

Oil filters all have paper filter elements, of one variety or another.

True, the Stilko filter had no bypass valve as all the off-the-shelf, single use filters do. I changed my oil often enough that it wasn't an issue, but I can see where it might be, in certain circumstances (like if you never change your oil...)

[dremd]

True,many full flow filters are cellulose (mine is cotton) but there is maybe a dozen or so times more cellulose in a roll of TP than any filter I know of.

You definatley don't want a bypass valve on a bypass oil filter (why they don't put them) you would just loose oil pressure & flow to bearrings with no added filtration.
And you definatley don't want a TP filter as full flow max flow is way way way to low.

All good stuff.
Best way to keep water out is still heat.