Topping off vs changing oil

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If you have a vehicle that consumes, say, 1 qt every 2000 miles, do you prefer to keep normal OCIs (whatever that may be for you), or extend them because you're replenishing with fresh oil more often?

What about if you're having to add 1 qt every 1000 miles?

One of our vehicles consumes 1 qt every ~1800 miles or so. It is driven about 14000 mi per year. I did the math and we'd use less oil overall if we did two oil changes per year (2x ~7000 mi) with more topping off vs. 3 oil changes per year (3x ~4700) with less topping off.
 
I may be a rare bitog member but I am pretty lazy with following any oil change interval. I just keep topping up and change it when its convenient or i remember too. I remember reading that every quart added extends the oil change interval an extra 1000 miles. So if you change your oil every 6000 miles but add one new quart every 2000 miles i think if my math is correct then technically your next oil change would be at 11,000 mles.
 
Doing an oil analysis at your normal OCI will determine the amount of metal(s) accumulating in your oil. This will help determine if an extended OCI works with your engine. Yeah, adding oil every X amount of miles will replenish the additive pack found in the oil but that doesn't take into account any fuel dilution or normal wear metals accumulating in your engine oil.
 
My lady's 98 Camry falls into the same boat here.

It burns 1 or 0.75 qt qt every 1 thousand miles after the first 1,000 - 1,200 miles.

I tend to change it in there every 3,500 miles but I have gone longer. And recently much longer like 8 thousand miles. Though I had added 4.5 qts in that mileage. The Camry has 3 and 5/8 oil capacity. So... Like your scenario it was like a oil change across that whole run.

In the case of the Camry it is better because it's old school port injected motor and obviously no turbo. So much added in my case I think I can do what I did during that 8 thousand mile run and it was ok.

Though I do prefer to change it every 3500 to 4000 miles like I have typically done before.

Of your vehicles are like the 98 Camry and are port injected old school motors... Then I think your plan could and would be just fine.
 
I would stick with the regular change interval unless I had a heavy oil drinker of around a quart in less than a thousand miles. I would then extend the interval another 2000 miles or so.
 
Honestly, I think either formula you’re thinking about will be fine. You have to consider that 7,000 miles on an oil change isn’t all that much anyway, plus you’re adding new oil along the way. And at this point I imagine the mileage is high...you’re not talking about a new car...chances are there may be other/bigger concerns coming that will end the life of that vehicle (tranny, rust, big repairs).
 
I've had a couple of oil analysis' done on oil burners that I extended the OCIs on. [ 12,000mi ]. Health of the oil and wear metals were very good. In my experience, if you are often adding oil, no need to change oil so often.

I have an old Dodge minivan that burns a little oil although I don't drive it much. About every 9 months, when it it's down to the add mark, I might siphon out a qt and add in 2 quarts to freshen it up. Oversized Fram Ultra filter stays on for at least 4 years 20,000+ miles.

No oil change removes all of the oil. When oil is consumed it appears to take most wear metals and contaminants with it. Not much difference between an oil change and frequent top ups. Draining the oil probably helps flush out sediment from the oil pan.
 
Why not determine why the vehicle is burning oil and fix it? Have you done the math on that vs sending quart after quart of oil out the tailpipe?
Not always practical on an older vehicle to save five dollars on a quart of oil every month or two.You can buy a lot of oil before coming close on tearing down an engine.
 
It's likely piston rings or valve seals, which is costly to fix at a shop.
Not always practical on an older vehicle to save five dollars on a quart of oil every month or two.You can buy a lot of oil before coming close on tearing down an engine.

Well, we don't know why it's burning oil. If it's a cheap fix then it might be worth because oil changes could go down from 3x/yr to 1x/yr.
 
Well, we don't know why it's burning oil. If it's a cheap fix then it might be worth because oil changes could go down from 3x/yr to 1x/yr.
A PCV issue is about all that would be economical to repair. Many do not have the ability to go inside an engine.
 
Blackstone just had an article on how top up impacts UOAs.

I’ll operate on the assumption warranty is not a concern.

I am sure there will be barbarians at the gate but given the presented circumstances and assuming your able to check and add when needed, I’d do one OCI per year with a quality oil. That amount of top up is significant.
 
I tend to lose respect for an engine that consumes up close to a quart per OCI, so it's going to get Supertech FS at about an 8k OCI and maybe even a few ugly looks as I pass by.
 
Just curious as to if you changed brands of oil to see if the oil consumption gets better or worse.
My experience is that if your vehicle uses more oil that it should, it's either worn out, leaking, getting sucked thru the pcv, or dumping gas into the oil. I've had good luck running a heavier oil to slow down consumption. I mentioned a few times here, about my wife's Equinox using a qt every 750 miles. It calls for 5/30 wt from GM. But by using 10/40 wt, it can go 1500 miles before needing to be topped off. To me it seems they recommend the wrong oil from the get go. Probably for emission reasons. I don't see how recommending an oil that disappears every 750 miles, is helping anything.,,,
 
My experience is that if your vehicle uses more oil that it should, it's either worn out, leaking, getting sucked thru the pcv, or dumping gas into the oil. I've had good luck running a heavier oil to slow down consumption. I mentioned a few times here, about my wife's Equinox using a qt every 750 miles. It calls for 5/30 wt from GM. But by using 10/40 wt, it can go 1500 miles before needing to be topped off. To me it seems they recommend the wrong oil from the get go. Probably for emission reasons. I don't see how recommending an oil that disappears every 750 miles, is helping anything.,,,
I was just curious. From all the info on others commenting on here or FB that they use oil with one brand and not another just made me curious.
 
Assuming the engine is clean and in good condition other than the oil consumption... if I'm adding that much oil between services, I would change the oil and filter once every year. Not sure if that means extending the normal service interval in your case, but it's what I would do.
 
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