I use my pickup only for work. I make like 5K per year with it. I used synthetic oil and 15k Bosch filter for experiment (Purolator). I didn't write time of oil change nor filter change but did write millage and as I know about 5K above it give me time.
So I changed oil at 120k in mid of 2013. Filter I replaced at 129K before two years. In that 4 years I add 7 liters/quarts of oil so basically replaced oil once completely and in theory should be good for 30k from primary 120K. Notice that filter should be capable per millage do 5k more. I replaced both this month at 140K.
Verdict in my case - it do NOT work. Time limit is real, not only millage. I felt much rougher driving last a few months. Replaced oil (synthetic again) and filter before 10 days and pickup engine work WOW again. First five days after replacement engine work was similar to before replacement. I guess new oil and filter needed time to clean whatsoever sludge is in engine. 10 days after replacement engine is working smooth as it get again.
So do not ignore time for filter and engine oil. I will replace both once one year from now on. Notice above I wrote "much rougher", it wasn't bad but it wasn't good aither. However bad enough to replace oil/filter once one year at all my cars and that EVEN WITH ADDING OIL PERIODICALLY TO ENGINE.
Edit and that is important. I did all time check oil color. It never was too bad, therefore I didn't change it. At day I replaced it was medium brown, not even dark brown, and per color looked good and I didn't feel any particle under finger. Bosch filter looked like new from inside when I toke it off.

 

What I just read was abuse of the motor. 5000 miles or not.
First rule is to run the truck long enough to fully heat and drive some of the evaporative impurities out.
Adding oil in lue of change does not get rid of acids that accumulate over the long term..
Filter does not take care of them. Filter is there to stop hard particles from circulating the bearing area.
You would not do this to a 3 valve motor and get away with it.

Good luck.

 

^^^ Pretty interesting answer. Definitely will have to google about acid aspect of oil change. To be more specific my average drive to project (I'm carpenter) is about 12 miles. So plenty time for engine to warm up. Another aspect that probably will keep in mind is I'm in MN weather. I'm aware that is better live truck then start it for only short time.

 

I completely agree with this. In fact I may go on and say that some (<-operative word) damage has already been done.

JMHO

 

FYI- acids in the oil are typically burned up within the first few minutes of operation....... the oil "additives' as I will call them, begin breaking down after 1,800 miles.....meaning although if you let your engine sit for longs periods in weather, that could have been a factor, there is a large host of other contaminets that were more highly prone to cause the damage...... also typical bypass type filters such as Franz, etc. are excellent and designed specifically for this purpose however they have always recommended (dating back to the 50's) changing their filter out every 30-60 days (criteria) and changing the oe filter out no less than annually.......and they filter down to 2-5 microns.

 

Oil is still in shed. I/m not sure abut yours opinions. Do not make me carring that oil to test lab.
Honestly I do not see reason why some damage already is bin done. I drove only 20K at synthetic oil where is added 7L at original capacity of 6L. Filter I replaced before time. Do not see reason for damage be done. Time schedule is evidently only problem in this case and open for discusion. I'm, again, aware that engine should be bring to full operating temperature after start and I do it regulary.

 

Thanks for the experiment however I wouldn't try it myself. It would be great to have an oil analysis to actually see how is. I drive approx. 5k miles per year on my truck and my oil change interval is every 5k miles or once a year.

 

Man, you high mileage drivers at 5k per year make my 1,500 look low.

I only put 1,500 or less on mine each year but it gets changed yearly if for no other reason than it makes me crawl under her and inspect things once a year.

 

Well, I am entitled to my opinion LOL, but it is based on experience. I was a professional mechanic for over a decade, built and campaigned race cars on regional tracks. I was also involved with the maintenance of my aircraft fleet (Cessenas and Pipers) and the unique requirements of those machines. My experience and research proved to me that oil does lose the lubricating properties that was "engineered" into it by the formulations created. No the oil itself doesn't break down, but the additives change/dissappear with the heat, acids, time, and impurities over time. Just look what happened when the powers that be decided to take out the zinc......

So yes, it is my opinion, but it is an educated one .... (yes I am an old fart)

 

If there weren't people doing experiments like these us old farts would never know what not to do..
My old opinion..

 

Been changing full syn (Mobil 1 in my chase) every 25K for the last 30 years. Put 325K on a 87 T-Bird without issues, 500K on a Volvo, currently have 300+K on a MB diesel, and 70K on my F150 4.2. Change the filter every 10K.

Never have had an oil related issue.

During 39 years in the Army oil changes were preformed based on oil analysis, never came in before 25K and usually extended to 50-75K. So I picked 25K as my point.

25K oil changes is four oil changes per 100K instead of 20. At over a million miles of driving that is 160 oil changes or savings of about $8-10K with my vehicles using fro 5 to 10 quarts per change and oil at $8/qt.

Now and then for S&G I do an oil analysis. I have never had one come back negative.

There is absolutely no data supporting a 5K oil change with full synthetic oil (not the BBB (yes Better Business Bureau) highly refined Dino Base III stock but full polyalphaolefins (PAOs) or ester synthetic Base IV stock). Lots of data is out there supporting oil changes out past 100K with filter changes and oil analysis.

Mobil 1 makes a 15K and annual oil, MTK makes a 30K oil.

And yes I am an old fart that remembers the oil wars of yester-year, first there was the detergent vs non-detergent oils and later single viscosity vs multi-viscosity oils, and now synthetics. My dad changed his oil religiously at 1K and the filter every 2K, what a laugh today. Technology has always won and in 20 years or so when all automotive oils are synthetic extended interval we will wonder what the fuss was all about.

 

Not only you are entitled for it, I post here to hear different opinions. Will carry oil for analysis somewhere if will not cost over 100$. Thanks "nrkmann" too. Very interesting opinion. "Nrkmann" how LONG oil sit in yours cars? Oil change TIME interval? And what was oil change time interval for army trucks?

 

Totally agree.
Oh what the heck. Going to inject my 2 cents worth. No, you folks haven't seen me, but been a member for some time. I'm not a old fart (yet), but getting there pretty quick being a little over the half century mark.
I've been turning my own wrenches for the better part of 35+ years (since before I was driving) on everything I own and have owned. daily drivers, hot rods, yard equipment, jet ski's, tractors, etc. I don't take anything to a shop except for new tires and balancing, and I'm by no means religious about oil changes.
I've been a Mobil 1 fan for almost 30 years, and love the stuff, but unfortunately my truck doesn't. Seams to run best on Quaker State.
Use Mobil 1 and Bosch filters in the Altima though. When we bought the 06 Altima with 10K, I called Mobil 1 to make sure I wasn't going to have any issues with the warranty, and I was informed that not only would there not be any issues, but if the engine experienced a oil related failure prior to the 100k mark (I think it was), and I was following their oil and filter change recommendations, they would replace the engine at no cost.
Change was 7k, but could go to 10k safely and new filter every 3k. Granted this was back in 06. This was also based on normal driving conditions, not sever (around town/stop and go and extended idling).
I was told that a very good rule of thumb for their pure synthetic oil is that when it starts getting dark, change it.

I could spout a whole bunch of crud about intervals and what happens to the oil, but you have Google.
My opinion is that if your doing a whole 5k annually, you need to be changing it and the filter annually, or at least the filter. When oil is dark, or black, it has a host of impurities and dilutants, and is not performing it's designed purpose.

 

Well, maybe I missed it, but what year and engine are we talking about here? Being an old fart myself, it could be my senility kicking in.

Still, recommended oil change intervals are extended according to recent manufacturer instructions. One of many articles should you Google the subject.
https://www.edmunds.com/car-news/tips-advice/stop-changing-your-oil.html

Now, I did catch the part about adding 7 quarts during the 4 year period. Sounds like high oil consumption over the 20k miles to me. So, did the extended interval do this damage? I don't know, but it seems unlikely as the oil level was maintained. Also noted you are using synthetic oil. If I am to believe the hoopla, this oil is not supposed to "break down" like Dino oil.

The fleet manager of the very large corporation I used to work for doubled the oil change interval. These trucks saw hard service in Canadian winters and racked up half a million kilometers before they were retired, usually in good running condition.

 

To re enter the thread, if the change intervals were done as NORMALLY recommended there likely would not be this thread.
A big difference between fleet use of a vehicle and one that is run so little no matter what oil is used and still has issues develope.
I don't disagree that full synthetic oil may be superior over the long term but on a short mileage basis it has not shown any advantage according to the original post.
For what its worth I have been using Motor Craft 5w20 Blend and 820S filter about every 5 to 6 k miles.
My opinion is the people who run extended intervals with different oils are taking a long term gamble just because others do it.
.
Manufacture engine testing to arrive at a 'practical' oil and interval is done in labs and with oil analysis where they can see what parts are wearing.
Then make changes in parts design and oil formulations until a engine normal life expectancy and change intervals are developed.
Why do people try to get around the original testing by guessing and doing what other are doing all on 'faith' without any scientific basis?
Simply have to remove the acids and contamination out of the engine by change intervals.
Gas has many chemicals in its formulation. Those chemicals change phase and combine with others along with combustion by products to generate the contamination. Oil has not as large part (it better not) in this but has to carry it in suspension and circulation.
Oil's sole purpose is the keep sliding/moving parts separated and cooled by circlation.
.
My 02 motor is at 271,000 and still runs perfect with the same performance it had when purchased at 33k.
The 02 body likely will fall apart before the motor gives up.
I would take my 271k mile experience over the 20k scenario with the top grade oil, any time.
I run a full time real oil pressure gauge. The pressures at cold, hot Idle and running at still at spec. Cold starts near 75 psi, hot idle at 25 and normal running at 50 psi.

Good luck.