For years I reused friends 'oil change oil of <5000KM'. Dang it was clean and 'tan' coloured. All I did was let it sit a month or so, siphon off the top, add to my truck, it ran fine..for years...

I think 'need oil changed every 5K' is more a SCAM to constantly get money out of your pocket,especially after reading the Tom McCahill tests he did in the late 60s. Pretty sure oils are better now than then...

My nephew has a Chevy Sierra with 390K on the original drivetrain. Does the same thing I do. He just repaired the rusty pickup bed, and put a rocker and a pair of cab corners on it. After he saw what they want for a new pickup, he said "fat chance" of him spending that kinda money on a new pickup! He repaired the rust, had his buddy blend in where he did the  repairs., and he's good ta' go....  

Don't ya' know Steve, EVERYTHING is a scam, except in Jaytopia, where nothing is a scam.  Jay invented copper wire when his left hand and right hand found a penny simultaneously.

Guys.. please find and READ Tom McCahills story/report/adventures on doing  oil tests in car in mechanix illustrated. From what I recall he and crew drove several cars ,1000s of miles. no oil change(top up)/filter, filter change only, oil and filter change. What mattered at the end of the test was to change the filters.

Now since engines and oils and filters 'should' have improved in the past 6 decades, you should be able to go FURTHER between oil changes NOT less. My '67 stang was done every 5000 MILES....now 'they' say every 5000 KILOMETERS.... hmmm, that's about 3,000 miles.

That's why I say 'scam' as it's NOT necessary

That being said, i do 5000 miles on everything.. Have for 50 years.

Dealer gave us free oil changes for 25000 miles.  Only changed the oil every 10,000 on it.  So that's what I do, full synthetic, high mileage.  Everything else gets changes at 5000 miles with regular oil.

A friend loves the full synthetic for his oil burner.  Says it's a lot cleaner so he doesn't have to clean it as often.

So how far do you go then?  In your F150?  In the wife's Nissan whateverthehellitwas?

I put less than 3000 miles on my F150, lot less due to the Chinese..

Wife's had 2 'free' oil change in 7,000KM...

WooooWeee there are some "old school" thoughts here.  Our Toyota goes 10K or one year on an oil change.  Has a lifetime power train warranty also.

Sure i used to change oil at 3K in my 57 chev.

Times, lubes and internal combustion engines have changed.

I am pushing 78 so it is never too late to change.  Man if I lived close to some of you oil wasters :), I could run forever on the good stuff you dump.

Um....Maybe I'm slow....How does that answer my question, which I thought was, how long BETWEEN OIL CHANGES for you.

I mean, I know I didn't say that, but oil change intervals was the topic at hand.

F150, 6000 miles,16 months ago was last one, not even close yet

Car ,3000 miles(they're free...)

BTW gas jumped up 20c a liter ,or 80 cents overnight....hmm it snowed, C was found guilty

Wow.......sigh.....so, How many miles do you PLAN to go between changes on the Ford F150????

And the car, it's free, but a scam.

I'm just trying to keep up here.

we don't have miles up here anymore...silly kilo-meters...it's a Liberal thing...

I only have 143,000 km(86,000 miles +-) on the truck...I was thinking 150,000, nice round,easy number, tough with the 'stay-at-home' lockdown(cops can arrest you !) until June, I can't even get to wallyWorld to buy oil ! Can't order online and have it shipped ( 'harardous goods' ) same BS for tubes of gasket making goop......It might actually be 2 years from now before I get even close to 150.

Last gas I bought was 1.13 per litre, it's now 1.21 at 10PM, 5 hrs ago 1.33....

Man the Chinese have really 'done a number' on us....

I retired, after 31 years, from NYS DOT as a general foreman. For many years before I retired, they used recycled oil. New trucks, that were still under warranty, got new oil until the warranty was up and then they were switched to the recycled oil. 

In all the years that I worked there, I never saw an engine that had an oil related failure, other than we had problems with plows (large dumps) a few years that the oil pans rusted through due to their high salt and calcium chloride exposure. 

Many of these trucks were kept until they had 300,000 miles, which I know isn't a lot for a large dump, but most of those miles were put on at 30 mph plowing snow or idling for hours on job sites.

DOT had a very good preventative maintenance program. Engine oil and filters were changed regularly.

I conclude, from that, that regular oil and filter changes are probably more important than using synthetic oil.

OK, let's see, translating Canadian to American, um, if I follow you correctly, let's see here, you have 143,000 km ( we have those here too, but, like furlongs, not used very often) and ya' plan (well, plan, yeah, strong word) to go to 150,000 because it's a nice round number......so....7000km which is.......wait for it......4349.597 miles!  Phhhhewwwww boy, yessir, you really are pushing the envelope!!!

In addition, the synthetics are formulated so as to not shear as easily, so they last longer.

FWIW. don't beat me up, I am just passing along what I have read  

yeah Coke the idiot is in bed with the Chineses...don't get me goin, but I've got 5 deer slugs ready just in case he walks down my road......

saw that google has over 10 million hits of how to reuse old engine oil,one that I read, the guy adds 3 recycled quarts to every new quart. some have fancy filter systems, some 'burn off' the 'junk'... common theme is that they are all time consuming and messy compared to having someone toss new filter and oil into your ride....

kinda wondering how  many guy actually replace the final drive oil in there tractors every year. D-14s only have a fill plug, no drain plug...hmm 2nd Q, why ????

warm and sunny here, lunch is over, hihohiho it's outside I go !

This oil change discussion has been going off and on for some time now.

The question I have especially for the 10k interval guys.

Do you check it periodically to see if it is staying in there to monitor if you might have a problem brewing.

I've seen it happen and I'm just asking.

fixer, I gotta yarn for you.

I am one of the old pfarts that used to wear out the drain plug.  But now at 77 plus and counting, I think I try to not get "set in my ways".  I change the Toyo at 10K.

Yeah and I do not check the oil every day cus times have changed and I do not hear the Pistons swapping cylinders"

I was once visiting my daughter on the east coast.  She had relegated the driving and upkeep of the old Rav 4 to the oldest grandson.

 I yanked the dipstick and low and behold there was no oil showing at 14 K since the last change and the grandy "said" he did not notice the service light was on.  However that noble beast was stilt getting him down the rod and everything was great.

So can these modern motors run with or without oil?

My trusty A-C forklift with a Buda diesel 4BD-153 engine in her, keeps on running. Excessive 'blowby',low compression(needs 3 squrits of ether) she runs like a top...

I've had every kind of 'oil' in her, SAE30, 10W30, 15W40,real,synth,semisynth,used,abused...whatever I have here, just 'topup' when oil pressure gets below 20# Added a few 'additives' like STP, BARDOL, etc., it's had 2 ,maybe 3 oil changes in 17 years. Last one, last summer,after I figured HOW to build ramps and platform to make it safe to get TO the oil plug... reminds me ,need to add some  oil soon...below 20  today(oil pressure NOT temperature !)

Odds are real good it'll outlive me.......

Had an '04 Monte Carlo.....pretty much the same thing.  I guess some things never change!

Engine oil does break down as Lou mentioned, and it also gets dirty from different driving conditions as Steve mentioned,  that's why I change my oil and filters frequently in my vehicles. Like Steve, I've been doin' that for 50 years myself. 

Coke had me laughing reading his post about the sludge. Dad had a 63' Chevy P/U he bought new in 63'.  Fast forward about 5-6 years. I came home from school one day and thought I would change the oil in Dad's truck cause' I knew he didn't change the oil much in it. Before I did anything, I pulled the dipstick  out of it just to see if it had any oil in it to begin with. The stick read full! Black, but full. Wow, its got oil in it! So I proceeded to get his drain pan that he didn't use, knock the plug out of the oil pan, and nothin' came out! WTH? Went back up, pulled the dipstick-Full.  Borrowed a coat hanger from Mom, stuck it up in the hole, and the oil started plopping out. Needless to say, I dropped the 100 lb. oil pan, (that I wasn't ready for laying on my back) and the same amount of sludge like Coke found in his customers oil pan. right up to the oil pump! Dad was pissed that I had dropped the pan till he saw all the black mud in the pan. After I got the oil pan on a diet, (it was much easier installing it)  Dad swore that old 235 inline six in that truck ran faster down the road.  LOL!!   

Steve@B&B

This is from the link below: "Most lubricating oils are formulated with chemical additives that enhance the beneficial properties of the base oil or make up for oil deficiencies. For passenger car motor oils, base oil makes up 70 to 80 percent of the final product; additives comprise the other 20 to 30 percent."

https://www.amsoil.com/newsstand/articles/the-role-of-additives-in-motor-oil/" rel="nofollow - The Role of Additives in Motor Oil Performance (amsoil.com)