I have a 1994 Toyota Corolla with over 300K miles on it. It burns or leaks a quart of oil about every 1500 miles, and I add a quart of Duralube maybe every 30,000 miles or so. However, in the over ten years that I’ve owned the car I have maybe only changed the oil five or six times. Indeed, partly out of an almost morbid fascianation/curiosity I have gone the last 100,000 miles without changing the oil (and who am I kidding just plain laziness). According to everything I read about cars this shouldn’t be possible. What’s more the engine seems to have about as much power as the day I bought it with 18,000 miles used from Budget Rent A Car.
What kind of oil did you put into it last? I ask, because Dean Ing is running the same sort of experiment with one of his cars, using a castor oil-based lubricant. It was up to 200k, last time I heard.
If you’re dumping fresh oil in every 1500 miles you are giving it a kinda-sorta oil change with the fresh oil . The only mystery is why your oil filter isn’t completely clogged.
Honestly, I find your story hard a bit hard to believe, and I honestly think you’re playing us to a large degree with some of your questions. You’re not an idiot, and I can’t imagine anyone other than a complete retard deliberately abusing a reliable car this way unless they’re pushing for it to fail. Given your current financial scenario, which your’ve discussed a few times, you can’t afford a new car at this time so your doing this “experiment” would make no contextual sense whatsoever given the financial and domestic picture you have painted in prior posts.
It just depends sometimes I add Valvoline, other times its Penzoil, it’s always 10W-30.
Look Dude, I normally don’t have an extral $30.00 to have it changed (and have no clue how to do it myself, and no garage (which was made into a room for my grandparents decades ago) in which to tinker. I have taken it to Miller’s in the past in Shelbyville to have the oil changed, but they always want to fix other things that I cannot afford. Besides I figure that it’s worked this long why “stir things up”. I probably will take it in sometime in the next month or so (only to hear Mr. Miller bitch at me that my oil looks something out of an X Files episode). As my wife would eagerly tell you I am one of the most pathetic, lazy, fXXXXX human beings on the planet.
I wouldn’t consider an engine that burns a quart of oil every 1500 miles to be in particularly good shape.
i had a beat up cavalier that leaked about a quart a month… i would frequently forget about that… and put oil in it when the oil light would come on… which whould then require about 2 quarts of oil to top it off. I too would also let it go wayyyyy over 3000 miles (though, no where in the neighborhood of 100k)… it ran until the day my X decided to smash the front AND back of the car by driving like an idiot. I put over 100k miles on it myself and it had 70k when i bought it for $500 
so, engines CAN last w/ low oil and infrequent changes… but if you got the money, it’s prolly better to play it safe.
You most likely have damage to the cylinders and/or pistons if you’re burning that much oil. You’re supposed to change it regularly to get rid of the crap that causes the damage. Eventually your engine is going to fail, and it will be very expensive to fix.
IIRC one auto manufacturer, maybe Ford considered burning 1 qt/900 miles is considered ‘normal’.
To the OP, unless you changed your oil filter, it has most likely broken through, and your engine is recirculating unfiltered oil. Also since your oil has not been changed, it most likely has more contaminated in it, which is getting circulated.
All in all, I would say that your oil has to be loosing effectivness, and is becomming less and less slippery, which will increase wear. I would expect it will fail in a imeadiate way as you see it. Meaning the amount of wear will be small at 1st, then accelerate to the point that once it is noticeable to you it’s too late.
To some degree the dirty oil may act as a polishing compound (much like the break-in oil that used to be used) and could actually appear to improve things for a bit, again eventually leadign to failure.
But then again it’s an old car, so no harm in letting it wear out, hopefully you won’t get stuck.
Another suggestion, perhaps you can donate your car to a college auto repair class or something to let the students see the effect of not changing the oil that long, back in college, I would have really liked the change to see that.
I had an elderly neighbor who did that…he would just change the filter every 3 months. Eventually, his car broke down. The mechanic took the oil pan off-and it was caked solid with engine sludge! Once sludge builds up in an engine, it is just a matter of time before a chunk ofit breaks loose, and blocks the oilpump. Then you have a blown engine! Although, I hear that cars runnng on LP gas never need oil changes-the LP gas doesn’t generate water and acids, so sludge doesn’t form in the crankcase.
Isn’t Shelbyville a town in The Simpsons? Are you Cartoonguy by any chance?
Oil changing instructions.
- Go to the auto parts store and get eight bottles of Kendall GT-1 Heavy Duty motor oil. ($8)
- Ask at the counter what oil filter fits your car. ($3)
- Get a strap-type oil filter wrench. ($3)
- Get a breaker bar and socket, the right size for your oil pan bolt. You can ask them to measure it if you don’t know the size ($11).
- Get an expendable 6-qt pan to drain the oil into. (50c)
- On a clear, dry, reasonably good day, go out to your car in the driveway.
- Slide your body under the car (DON’T PUT IT ON THE JACK! IF YOU’VE GOT JACKSTANDS USE THEM OTHERWISE YOU’RE A HELL OF A LOT BETTER OFF DOING THIS WITH THE CAR FLAT ON THE GROUND).
- Slide the pan under the sump plug.
- Using the breaker bar and socket, remove the oil plug. Make sure it doesn’t point at your eyes.
- Let the oil drain. Rock the car from side to side until it stops draining.
- Find the oil filter. Remove it using the filter wrench over the pan and tip it into the pan.
- Open one of the bottles of oil. Put your finger in it and rub the oil over the seal on the new oil filter.
- Spin the new oil filter on hand tight, no more.
- Re-install the oil drain plug.
- Open the oil filler cap on the top of the engine and pour three quarts of oil into it.
- Take a look at the dipstick. If the oil doesn’t show up on it, add another quart.
- Add oil until it’s right in the middle of the dipstick.
- Get in the car and drive to a gas station or the auto parts store, depending on which one accepts used oil. If you’ve got an oil-burning furnace, you can pour the used oil into the tank, but whatever you do, don’t pour it out on the ground. Used oil is both acutely toxic and carcinogenic if it gets to the water table.
- In the parking lot of the store, check the oil filter to see if it’s still tight. If it isn’t, tighten it again.
- Check the oil level. You’ve cleared out all the junk that was sealing up the smaller oil leaks and some of the passageways in the engine; it’ll use some in the first few miles. Add oil to keep it full.
- This first oil change will probably take about an hour. Your second will take 30 minutes. Your third will take 15. Your fourth will take ten. Do this every 5,000 miles. It’s nine bucks - if you can’t afford that, can you afford $999 for another car?
Does anyone think that the Duralube every 30,000 miles or so might be playing a role in extending engine life?
Is there any point in starting to change the oil regularly now given how long I’ve gone without doing so?
Also, I may eventually donate the car. However, I actually intended to make it a “permanent car” meaning that I would just fix whatever goes wrong (as it breaks including engines) forever. Keep in mind that the only preventative maintenance that I’ve ever done was a new timing belt at around 180K miles or so. I took the car into a Toyota dealership at about 100K miles and they wanted to do $900.00 dollars in belts, hoses, valves and other maintenance. I said no and have not done any maintenence of this sort since. Also, it’s a stick shift (I have replaced one clutch) so at least I don’t have to worry about the AT going out. The hood has a few very small rust patches which I would like to fix, but am not sure how to go about doing so (I bought some stuff that supposedly converts the rust to metal, but I’m not sure if I should sand first ect).
If you’re adding a quart every 1500 miles, you’re basically changing all the oil every 6000 miles. The filter has probably clogged up and is being by-passed by the engine. The other tolerances are probably so loose from 200k miles that dirt probably just passes through. If you took your oil pan off you’d probably see an inch and a half of crud in the bottom of the pan. You probably only have about two quarts of oil really in the engine. You’ll eventually clog up the oil pick up tube and then have no oil pressure and the engine will die.
I am not a mechanic, but at this point, assuming most of the mileage was not longer trips, I don’t believe a move to frequent oil changes would increase total life span of your vehicle that much.
Some cars do last 300,000 or more miles, but that’s well beyond the average already. Are the doors wearing out yet? I had a Dodge Colt, the engine might have continued for decades but most of the body rusted out before that. I could possibly now still be driving it if I wanted to drive around town without doors, windows etc.
I too have a couple of vehicles that have not had the oil replaced in years.
The 90 oldsmobile ran until my daughter blew it up 2 months after she got her licence. FWIW she was clocked driving 75 mph in a 55 mile zone by her mother one time so I think I know why the car which had 300K + miles failed.
My 88 S10 whose speedometer quit 10 years ago shows 135K. It was driven every day until my hip operation when I bought a Sonoma with an automatic transmission.
Although I don’t recommend treating vehicles this way its amazing that they keep running. OR is it just a lot of hype that oil must be changed as often as we’ve been led to believe.
I’m guessing its the latter.
Lets do some figuring.
As stated above it costs $9.00 to change oil-actual cost.
Do that for the life of the car in these cases 300K every 3K thats $900 plus labor which above figured about $20.00 for the life of the car is $2000.00. So you have $2900.00 in just oil changes.
Gee I wonder what I did with all that money that I saved especially since both vehicles were not supposed to run as long as they did.
I’d blame its longevity on the fact that its a Toyota. Toyota still hasn’t caught on that in order to be successful in the American auto market, you have to build cars poorly, ones that don’t last forever. The 1983 Toyota pickups were the stupidest thing Toyota ever did, from a bottom-line standpoint - they last forever, and you can’t kill them. 
Why is non-detergent motor oil still sold? All of the mechanics I know tell me that since the advent of modern, high-detergent engine oils (and frequent oil/filter changes) engine sludge is a thing of the past. Yet, as recently as a few years ago, I still recall seeing brands like Gulf “Sapphire” non-detergent oil. It was maybe $0.25 a quart cheaper-so why is the stuff still made?
IIRC Clark Howard has reported that very few cars actually need an oil change every 3,000 miles. Most can go 5-7,500 with no significant change in the performance or life span of the car.